How to reload PowerShell path after setting it? [duplicate] - windows

If I have an instance of PowerShell ISE running and I install something that modifies the PATH or I modify it in any way outside of PowerShell then I need to restart PowerShell for it to see the updated PATH variable.
Is there a way to reload the path from within PowerShell without restarting it?

Just to bring Rob's comment to light:
$env:Path = [System.Environment]::GetEnvironmentVariable("Path","Machine") + ";" + [System.Environment]::GetEnvironmentVariable("Path","User")

Try getting the machine path and assigning it to the session's path.
$env:Path = [System.Environment]::GetEnvironmentVariable("Path","Machine")

Easiest way, use Chocolatey (freeware). It works for both CMD and PowerShell. Then you will be able to reload PATH (with variable expansion) with a simple command:
refreshenv
Installation from cmd (requires administrator rights):
#"%SystemRoot%\System32\WindowsPowerShell\v1.0\powershell.exe" -NoProfile -InputFormat None -ExecutionPolicy Bypass -Command "iex ((New-Object System.Net.WebClient).DownloadString('https://chocolatey.org/install.ps1'))" && SET "PATH=%PATH%;%ALLUSERSPROFILE%\chocolatey\bin"
Example usage:
> SET JAVA_HOME=c:/java/jdk6
> SET PATH=%JAVA_HOME%/bin
> ECHO %PATH%
c:/java/jdk6/bin
> SET JAVA_HOME=c:/java/jdk8
> refreshenv
Refreshing environment variables from registry for cmd.exe. Please wait...Finished..
> echo %PATH%
c:/java/jdk8/bin

Based on mpen's answer, here is a PowerShell function:
function refresh-path {
$env:Path = [System.Environment]::GetEnvironmentVariable("Path","Machine") +
";" +
[System.Environment]::GetEnvironmentVariable("Path","User")
}
Then just call refresh-path.

Just to add to other answers, you can make sure you don't add superfluous joins by filtering in case the user has an empty path.
$env:Path=(
[System.Environment]::GetEnvironmentVariable("Path","Machine"),
[System.Environment]::GetEnvironmentVariable("Path","User")
) -match '.' -join ';'
Or, more usefully, if you're running a script that adds to a different or multiple environment variables, use a function to reset them all
function resetEnv {
Set-Item `
-Path (('Env:', $args[0]) -join '') `
-Value ((
[System.Environment]::GetEnvironmentVariable($args[0], "Machine"),
[System.Environment]::GetEnvironmentVariable($args[0], "User")
) -match '.' -join ';')
}
resetEnv Path
resetEnv AppPath

If your path contains environment variables that weren't defined at the start of the session, you'll want to expand those too:
$env:Path = [System.Environment]::ExpandEnvironmentVariables([System.Environment]::GetEnvironmentVariable("Path","Machine") + ";" + [System.Environment]::GetEnvironmentVariable("Path","User"))
For me this was useful after installing NVM which defines and adds %NVM_HOME% to the path.
To take this to its logical conclusion you could use this recursive function to expand instead:
function Expand-EnvironmentVariablesRecursively($unexpanded) {
$previous = ''
$expanded = $unexpanded
while($previous -ne $expanded) {
$previous = $expanded
$expanded = [System.Environment]::ExpandEnvironmentVariables($previous)
}
return $expanded
}
And then use:
$env:Path = Expand-EnvironmentVariablesRecursively([System.Environment]::GetEnvironmentVariable("Path","Machine") + ";" + [System.Environment]::GetEnvironmentVariable("Path","User"))
I've opened an issue to add this solution into refreshenv from Chocolatey.

Related

How to install Rust using power shell?

I want to install rust automatically via command line on Windows. It doesn't matter if it's power shell or not but I think power shell is the easiest without having to install other stuff manually.
I found https://www.powershellgallery.com/packages/AppVeyorBYOC/1.0.170/Content/scripts%5CWindows%5Cinstall_rust.ps1 but at
Add-SessionPath "$env:USERPROFILE\.cargo\bin"
it says that Add-SessionPath is a cmdlet that does not exist.
I had the same error. I changed that line to this and the script worked with Powershell 7.
$env:Path = "$env:USERPROFILE\.cargo\bin"
# Make new environment variables available in the current PowerShell session:
function reload {
foreach($level in "Machine","User") {
[Environment]::GetEnvironmentVariables($level).GetEnumerator() | % {
# For Path variables, append the new values, if they're not already in there
if($_.Name -match 'Path$') {
$_.Value = ($((Get-Content "Env:$($_.Name)") + ";$($_.Value)") -split ';' | Select -unique) -join ';'
}
$_
} | Set-Content -Path { "Env:$($_.Name)" }
}
}
Write-Host "Installing Rust..." -ForegroundColor Cyan
$exePath = "$env:TEMP\rustup-init.exe"
Write-Host "Downloading..."
(New-Object Net.WebClient).DownloadFile('https://static.rust-lang.org/rustup/dist/x86_64-pc-windows-msvc/rustup-init.exe', $exePath)
Write-Host "Installing..."
cmd /c start /wait $exePath -y
Remove-Item $exePath
$addPath = "$env:USERPROFILE\.cargo\bin"
[Environment]::SetEnvironmentVariable
($addPath, $env:Path, [System.EnvironmentVariableTarget]::Machine)
reload
cargo --version
rustup --version
rustc --version

executing uninstall string with powershell

I am trying to make a Powershell script for uninstalling software.
Here is the code:
$software = Read-Host "Software you want to remove"
$paths = 'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall', 'HKLM:\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall'
Get-ChildItem $paths |
Where-Object{ $_.GetValue('DisplayName') -match "$software" } |
ForEach-Object{
$uninstallString = $_.GetValue('UninstallString') + ' /quiet /norestart'
Write-Host $uninstallString
& "C:\Windows\SYSTEM32\cmd.exe" /c $uninstallString
}
it works good for uninstall strings like
MsiExec.exe /X{C22F57FC-4B20-3354-8626-382E3C710B38} /quiet /norestart
But if I want to uninstall something like winrar which have uninstall strings like
C:\Program Files\WinRAR\uninstall.exe
I get the following error
cmd.exe : 'C:\Program' is not recognized as an internal or external command,
any idea please how to get this script working
Regards
The problem is that you're unconditionally appending /quiet /norestart.
The solution is to test if the uninstall string as a whole refers to an executable file:
$isExeOnly = Test-Path -LiteralPath $uninstallString
Based on that, you can decide how you want to handle such executables:
If you simply want to execute them without arguments:
$uninstallString = $_.GetValue('UninstallString')
$isExeOnly = Test-Path -LiteralPath $uninstallString
if (-not $isExeOnly) { $uninstallString += ' /quiet /norestart' }
If you do want to pass arguments /quiet /norestart - though note that the target executable may refuse to execute if it doesn't understand these arguments:
$uninstallString = $_.GetValue('UninstallString')
$isExeOnly = Test-Path -LiteralPath $uninstallString
if ($isExeOnly) { $uninstallString = "`"$uninstallString`"" }
$uninstallString += ' /quiet /norestart'
The alternative is to special-case the arguments (options) to pass based on the executable file name (Split-Path -Leaf $uninstallString), but that is obviously cumbersome and impossible to do comprehensively.
Uninstall-package works with msi installs.
For non-msi installs:
You'd have to find out the silent uninstall options for winrar. It might be '/S'. (A quick google says it is.)
get-package *winrar* | % { & $_.metadata['uninstallstring'] /S }
Sometimes you have to get rid of literal double quotes:
get-package *winrar* | % { & ($_.metadata['uninstallstring'] -replace '"') /S }
Here's an attempt of a general answer for non-msi installs where part of the uninstallstring may or may not be in double-quotes:
$uninstall = get-package whatever | % { $_.metadata['uninstallstring'] }
$prog, $myargs = $uninstall | select-string '("[^"]*"|\S)+' -AllMatches |
% matches | % value
$prog = $prog -replace '"',$null
$myargs += '/S' # whatever silent uninstall option
& $prog $myargs

Determine local path of a TFS Workspace via tf.exe

I am using a batch script for getting the latest version of specific projects. This script only runs tf.exe and gets the latest version of some Binaries. Everything works fine, but I would like to change the attrib of the downloaded files to be writeable (by deafult these files are read-only). For that I want to determine the local path of the files and use the attrib-command from batch.
tf.exe workfold [Workspace] shows me the local path in some kind of listing but it would be easier, if it only shows me what I want so I can use the prompt. Until now the it looks like this:
tf.exe workfold [Workspace]
=======================================
Arbeitsbereich: XYZ-xxxxxx (Username)
Auflistung: TFS-URL
[Workspace]: C:\xxx\TFS\xxx
Is it possible to determine only the local path mapping of a TFS Workspace so that I can use the prompt for the attrib-command without parsing?
What about the following (crude!!!) concept?
function Get-TfsWorkfold([string]$TfsCollection, [string]$TfsWorkspace)
{
$TfExePath = "${env:ProgramFiles(x86)}\Microsoft Visual Studio 10.0\Common7\IDE\TF.exe"
Write-Output "Getting workfold for '$TfsCollection'->'$TfsWorkspace'..."
Push-Location $LocalPath
& "$TfExePath" workfold /collection:$TfsCollection /workspace:$TfsWorkspace
}
function Handle-Path()
{
param([Parameter(ValueFromPipeline=$true,Position=0)] [string] $line)
$startIndex = $line.IndexOf(': ') + 2;
$correctedLine = $line.subString($startIndex, $line.length - $startIndex - 1);
Write-Output $correctedLine;
Get-ChildItem $correctedLine
}
Get-TfsWorkfold "{serverAndcollection}" "{workspace}" > c:\temp\test.txt
Select-String c:\temp\test.txt -pattern:': ' | Select-Object Line | Handle-Path
The last line in Handle-Path is the example which you can rewirte with whatever you want to. It is PowerShell but it should work as you want.
Replace {serverAndcollection} and {workspace}.
Real men do it in one line
powershell -command "& {tf workfold | Select-String -pattern:' $' -SimpleMatch | Select-Object Line | ForEach-Object {$startIndex = $_.Line.IndexOf(': ') + 2; $_.Line.subString($startIndex, $_.Line.length - $startIndex - 1)}}"
Current answer will only return one last path if there are many.
You can also do it without any string manipulation, with calls to TF.exe. I have wrapped that in PowerShell scripts, so you get the following:
function Add-TfsTypes
{
# NOTE: Not all of the below are needed, but these are all the assemblies we load at the moment. Please note that especially NewtonSoft dll MUST be loaded first!
$PathToAssemblies = "C:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\IDE\CommonExtensions\Microsoft\TeamFoundation\Team Explorer"
Add-Type -Path "$PathToAssemblies\NewtonSoft.Json.dll"
Add-Type -Path "$PathToAssemblies\System.Net.http.formatting.dll"
Add-Type -Path "$PathToAssemblies\Microsoft.TeamFoundation.Client.dll"
Add-Type -Path "$PathToAssemblies\Microsoft.TeamFoundation.Common.dll"
Add-Type -Path "$PathToAssemblies\Microsoft.TeamFoundation.VersionControl.Client.dll"
Add-Type -Path "$PathToAssemblies\Microsoft.TeamFoundation.WorkItemTracking.Client.dll"
}
function Get-TfsServerPathFromLocalPath {
param(
[parameter(Mandatory=$true)][string]$LocalPath,
[switch]$LoadTfsTypes
)
if ($LoadTfsTypes) {
Add-TfsTypes # Loads dlls
}
$workspaceInfo = [Microsoft.TeamFoundation.VersionControl.Client.Workstation]::Current.GetLocalWorkspaceInfo($LocalPath)
$server = New-Object Microsoft.TeamFoundation.Client.TfsTeamProjectCollection $workspaceInfo.ServerUri
$workspace = $workspaceInfo.GetWorkspace($server)
return $workspace.GetServerItemForLocalItem($LocalPath)
}
The above method can then be called like this:
$serverFolderPath = Get-TfsServerPathFromLocalPath $folderPath -LoadTfsTypes
$anotherServerPath = Get-TfsServerPathFromLocalPath $anotherItemToTestPathOn

How can I use a powershell-function in multi-script?

My C#-program should be by opening perform a powershellfunction, looks like this:
function RunIE
{
$a = Get-ItemProperty HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion -name ProgramFilesDir
$path = $a.ProgramFilesDir + "\Internet Explorer\iexplore.exe"
& $path "www.heise.de" -extoff
Start-Sleep 6
$shell = (New-Object -COM Shell.Application)
$ie = #($shell.Application.Windows()) | Where-Object { $_.LocationUrl -like "*heise*" }
Write-Output $ie
}
$ScriptLog.Invoke([log4net.Core.Level]::Debug, "Funktionsdurchlauf durchgeführt")
The log at the end will written in my logfile. (So I think this works.)
During the C#-program runs an other script should be conducted, like this:
...
$ie = RunIE
#here I get a mistake: "The term 'RunIE' is not recognized as the name of a
#cmdlet, function, script file, or operable program. Check the spelling of the
#name, or if a path was included, verify that the path is correct and try again."
$ie.Navigate2($path)
Start-Sleep 5
...
How can I use my function in other scripts, without new/second invocation? (I think the solution must create in powershell.)
thanks.
You need to dot source the script that contain the functions and script-scope variables you want to use in your script. For instance, if IEUtils.ps1 contained your RunIE function then you would dot source it into primary script like so:
. C:\Temp\IEUtils.ps1
$ie = RunIE
This assumes that IEUtils.ps1 in C:\Temp. Subtitute the appropriate dir as required. If it is in the same dir as your primary script then use:
$ScriptPath = $MyInvocation.MyCommand.Path
$ScriptDir = Split-Path -parent $ScriptPath
. $ScriptDir\IEUtils.ps1

Setting Windows PowerShell environment variables

I have found out that setting the PATH environment variable affects only the old command prompt. PowerShell seems to have different environment settings. How do I change the environment variables for PowerShell (v1)?
Note:
I want to make my changes permanent, so I don't have to set it every time I run PowerShell. Does PowerShell have a profile file? Something like Bash profile on Unix?
If, some time during a PowerShell session, you need to see or to temporarily modify the PATH environment variable , you can type one of these commands:
$env:Path # shows the actual content
$env:Path = 'C:\foo;' + $env:Path # attach to the beginning
$env:Path += ';C:\foo' # attach to the end
Changing the actual environment variables can be done by
using the env: namespace / drive information. For example, this
code will update the path environment variable:
$env:Path = "SomeRandomPath"; (replaces existing path)
$env:Path += ";SomeRandomPath" (appends to existing path)
Making change permanent
There are ways to make environment settings permanent, but
if you are only using them from PowerShell, it's probably
a lot better to use Powershell profiles script.
Everytime a new instance of Powershell starts, it look for specific script files (named profile files) and execute them if they do exist. You can edit one of these profile to customize your enviroment.
To know where those profile scripts are located in your computer type:
$profile
$profile.AllUsersAllHosts
$profile.AllUsersCurrentHost
$profile.CurrentUserAllHosts
$profile.CurrentUserCurrentHost
You can edit one of them, for example, by typing:
notepad $profile
You can also modify user/system environment variables permanently (i.e. will be persistent across shell restarts) with the following:
Modify a system environment variable
[Environment]::SetEnvironmentVariable
("Path", $env:Path, [System.EnvironmentVariableTarget]::Machine)
Modify a user environment variable
[Environment]::SetEnvironmentVariable
("INCLUDE", $env:INCLUDE, [System.EnvironmentVariableTarget]::User)
Usage from comments - add to the system environment variable
[Environment]::SetEnvironmentVariable(
"Path",
[Environment]::GetEnvironmentVariable("Path", [EnvironmentVariableTarget]::Machine) + ";C:\bin",
[EnvironmentVariableTarget]::Machine)
String based solution is also possible if you don't want to write types
[Environment]::SetEnvironmentVariable("Path", $env:Path + ";C:\bin", "Machine")
WARNING: save a copy of your existing path by doing $env:path >> a.out in a PowerShell prompt, in case something goes wrong.
From the PowerShell prompt:
setx PATH "$env:path;\the\directory\to\add" -m
You should then see the text:
SUCCESS: Specified value was saved.
Restart your session, and the variable will be available. setx can also be used to set arbitrary variables. Type setx /? at the prompt for documentation.
Like JeanT's answer, I wanted an abstraction around adding to the path. Unlike JeanT's answer I needed it to run without user interaction. Other behavior I was looking for:
Updates $env:Path so the change takes effect in the current session
Persists the environment variable change for future sessions
Doesn't add a duplicate path when the same path already exists
In case it's useful, here it is:
function Add-EnvPath {
param(
[Parameter(Mandatory=$true)]
[string] $Path,
[ValidateSet('Machine', 'User', 'Session')]
[string] $Container = 'Session'
)
if ($Container -ne 'Session') {
$containerMapping = #{
Machine = [EnvironmentVariableTarget]::Machine
User = [EnvironmentVariableTarget]::User
}
$containerType = $containerMapping[$Container]
$persistedPaths = [Environment]::GetEnvironmentVariable('Path', $containerType) -split ';'
if ($persistedPaths -notcontains $Path) {
$persistedPaths = $persistedPaths + $Path | where { $_ }
[Environment]::SetEnvironmentVariable('Path', $persistedPaths -join ';', $containerType)
}
}
$envPaths = $env:Path -split ';'
if ($envPaths -notcontains $Path) {
$envPaths = $envPaths + $Path | where { $_ }
$env:Path = $envPaths -join ';'
}
}
Check out my gist for the corresponding Remove-EnvPath function.
Pain-free, one-line, example solutions
Try these three commands to practice setting and deleting environmental variables in PowerShell.
Notes on usage:
Run these commands on elevated PowerShell (e.g. with administrator privileges).
After every step, to make your commands work, close the session and open it again.
Add/create a permanent environment variable:
[Environment]::SetEnvironmentVariable("MyEnvVar", "NewEnvValue", "Machine")
Machine is an EnvironmentVariableTarget that will apply to current and future users, as opposed to the User target.
Modify/change environmental variable:
[Environment]::SetEnvironmentVariable("MyEnvVar", "NewerEnvValue", "Machine")
Delete/remove variable:
[Environment]::SetEnvironmentVariable("MyEnvVar", "", "Machine")
All the answers suggesting a permanent change have the same problem: They break the path registry value.
SetEnvironmentVariable turns the REG_EXPAND_SZ value %SystemRoot%\system32 into a REG_SZ value of C:\Windows\system32.
Any other variables in the path are lost as well. Adding new ones using %myNewPath% won't work any more.
Here's a script Set-PathVariable.ps1 that I use to address this problem:
[CmdletBinding(SupportsShouldProcess=$true)]
param(
[parameter(Mandatory=$true)]
[string]$NewLocation)
Begin
{
#requires –runasadministrator
$regPath = "SYSTEM\CurrentControlSet\Control\Session Manager\Environment"
$hklm = [Microsoft.Win32.Registry]::LocalMachine
Function GetOldPath()
{
$regKey = $hklm.OpenSubKey($regPath, $FALSE)
$envpath = $regKey.GetValue("Path", "", [Microsoft.Win32.RegistryValueOptions]::DoNotExpandEnvironmentNames)
return $envPath
}
}
Process
{
# Win32API error codes
$ERROR_SUCCESS = 0
$ERROR_DUP_NAME = 34
$ERROR_INVALID_DATA = 13
$NewLocation = $NewLocation.Trim();
If ($NewLocation -eq "" -or $NewLocation -eq $null)
{
Exit $ERROR_INVALID_DATA
}
[string]$oldPath = GetOldPath
Write-Verbose "Old Path: $oldPath"
# Check whether the new location is already in the path
$parts = $oldPath.split(";")
If ($parts -contains $NewLocation)
{
Write-Warning "The new location is already in the path"
Exit $ERROR_DUP_NAME
}
# Build the new path, make sure we don't have double semicolons
$newPath = $oldPath + ";" + $NewLocation
$newPath = $newPath -replace ";;",""
if ($pscmdlet.ShouldProcess("%Path%", "Add $NewLocation")){
# Add to the current session
$env:path += ";$NewLocation"
# Save into registry
$regKey = $hklm.OpenSubKey($regPath, $True)
$regKey.SetValue("Path", $newPath, [Microsoft.Win32.RegistryValueKind]::ExpandString)
Write-Output "The operation completed successfully."
}
Exit $ERROR_SUCCESS
}
I explain the problem in more detail in a blog post.
Although the current accepted answer works in the sense that the path variable gets permanently updated from the context of PowerShell, it doesn't actually update the environment variable stored in the Windows registry.
To achieve that, you can obviously use PowerShell as well:
$oldPath=(Get-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment' -Name PATH).Path
$newPath=$oldPath+’;C:\NewFolderToAddToTheList\’
Set-ItemProperty -Path 'Registry::HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment' -Name PATH –Value $newPath
More information is in blog post Use PowerShell to Modify Your Environmental Path
If you use PowerShell community extensions, the proper command to add a path to the environment variable path is:
Add-PathVariable "C:\NewFolderToAddToTheList" -Target Machine
This sets the path for the current session and prompts the user to add it permanently:
function Set-Path {
param([string]$x)
$Env:Path+= ";" + $x
Write-Output $Env:Path
$write = Read-Host 'Set PATH permanently ? (yes|no)'
if ($write -eq "yes")
{
[Environment]::SetEnvironmentVariable("Path",$env:Path, [System.EnvironmentVariableTarget]::User)
Write-Output 'PATH updated'
}
}
You can add this function to your default profile, (Microsoft.PowerShell_profile.ps1), usually located at %USERPROFILE%\Documents\WindowsPowerShell.
Building on #Michael Kropat's answer I added a parameter to prepend the new path to the existing PATHvariable and a check to avoid the addition of a non-existing path:
function Add-EnvPath {
param(
[Parameter(Mandatory=$true)]
[string] $Path,
[ValidateSet('Machine', 'User', 'Session')]
[string] $Container = 'Session',
[Parameter(Mandatory=$False)]
[Switch] $Prepend
)
if (Test-Path -path "$Path") {
if ($Container -ne 'Session') {
$containerMapping = #{
Machine = [EnvironmentVariableTarget]::Machine
User = [EnvironmentVariableTarget]::User
}
$containerType = $containerMapping[$Container]
$persistedPaths = [Environment]::GetEnvironmentVariable('Path', $containerType) -split ';'
if ($persistedPaths -notcontains $Path) {
if ($Prepend) {
$persistedPaths = ,$Path + $persistedPaths | where { $_ }
[Environment]::SetEnvironmentVariable('Path', $persistedPaths -join ';', $containerType)
}
else {
$persistedPaths = $persistedPaths + $Path | where { $_ }
[Environment]::SetEnvironmentVariable('Path', $persistedPaths -join ';', $containerType)
}
}
}
$envPaths = $env:Path -split ';'
if ($envPaths -notcontains $Path) {
if ($Prepend) {
$envPaths = ,$Path + $envPaths | where { $_ }
$env:Path = $envPaths -join ';'
}
else {
$envPaths = $envPaths + $Path | where { $_ }
$env:Path = $envPaths -join ';'
}
}
}
}
My suggestion is this one:
I have tested this to add C:\oracle\x64\bin to environment variable Path permanently and this works fine.
$ENV:PATH
The first way is simply to do:
$ENV:PATH=”$ENV:PATH;c:\path\to\folder”
But this change isn’t permanent. $env:path will default back to what it was before as soon as you close your PowerShell terminal and reopen it again. That’s because you have applied the change at the session level and not at the source level (which is the registry level). To view the global value of $env:path, do:
Get-ItemProperty -Path ‘Registry::HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment’ -Name PATH
Or more specifically:
(Get-ItemProperty -Path ‘Registry::HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment’ -Name PATH).path
Now to change this, first we capture the original path that needs to be modified:
$oldpath = (Get-ItemProperty -Path ‘Registry::HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment’ -Name PATH).path
Now we define what the new path should look like. In this case we are appending a new folder:
$newpath = “$oldpath;c:\path\to\folder”
Note: Be sure that the $newpath looks how you want it to look. If not, then you could damage your OS.
Now apply the new value:
Set-ItemProperty -Path ‘Registry::HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment’ -Name PATH -Value $newPath
Now do one final check that it looks like how you expect it to:
(Get-ItemProperty -Path ‘Registry::HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment’ -Name PATH).Path
You can now restart your PowerShell terminal (or even reboot the machine) and see that it doesn’t rollback to its old value again.
Note the ordering of the paths may change so that it’s in alphabetical order, so make sure you check the whole line. To make it easier, you can split the output into rows by using the semi-colon as a delimiter:
($env:path).split(“;”)
Only the answers that push the value into the registry affect a permanent change (so the majority of answers on this thread, including the accepted answer, do not permanently affect the Path).
The following function works for both Path / PSModulePath and for User / System types. It will also add the new path to the current session by default.
function AddTo-Path {
param (
[string]$PathToAdd,
[Parameter(Mandatory=$true)][ValidateSet('System','User')][string]$UserType,
[Parameter(Mandatory=$true)][ValidateSet('Path','PSModulePath')][string]$PathType
)
# AddTo-Path "C:\XXX" "PSModulePath" 'System'
if ($UserType -eq "System" ) { $RegPropertyLocation = 'HKLM:\System\CurrentControlSet\Control\Session Manager\Environment' }
if ($UserType -eq "User" ) { $RegPropertyLocation = 'HKCU:\Environment' } # also note: Registry::HKEY_LOCAL_MACHINE\ format
$PathOld = (Get-ItemProperty -Path $RegPropertyLocation -Name $PathType).$PathType
"`n$UserType $PathType Before:`n$PathOld`n"
$PathArray = $PathOld -Split ";" -replace "\\+$", ""
if ($PathArray -notcontains $PathToAdd) {
"$UserType $PathType Now:" # ; sleep -Milliseconds 100 # Might need pause to prevent text being after Path output(!)
$PathNew = "$PathOld;$PathToAdd"
Set-ItemProperty -Path $RegPropertyLocation -Name $PathType -Value $PathNew
Get-ItemProperty -Path $RegPropertyLocation -Name $PathType | select -ExpandProperty $PathType
if ($PathType -eq "Path") { $env:Path += ";$PathToAdd" } # Add to Path also for this current session
if ($PathType -eq "PSModulePath") { $env:PSModulePath += ";$PathToAdd" } # Add to PSModulePath also for this current session
"`n$PathToAdd has been added to the $UserType $PathType"
}
else {
"'$PathToAdd' is already in the $UserType $PathType. Nothing to do."
}
}
# Add "C:\XXX" to User Path (but only if not already present)
AddTo-Path "C:\XXX" "User" "Path"
# Just show the current status by putting an empty path
AddTo-Path "" "User" "Path"
Within PowerShell, one can navigate to the environment variable directory by typing:
Set-Location Env:
This will bring you to the Env:> directory. From within this directory:
To see all environment variables, type:
Env:\> Get-ChildItem
To see a specific environment variable, type:
Env:\> $Env:<variable name>, e.g. $Env:Path
To set an environment variable, type:
Env:\> $Env:<variable name> = "<new-value>", e.g. $Env:Path="C:\Users\"
To remove an environment variable, type:
Env:\> remove-item Env:<variable name>, e.g. remove-item Env:SECRET_KEY
More information is in About Environment Variables.
As Jonathan Leaders mentioned here, it is important to run the command/script elevated to be able to change environment variables for 'machine', but running some commands elevated doesn't have to be done with the Community Extensions, so I'd like to modify and extend JeanT's answer in a way, that changing machine variables also can be performed even if the script itself isn't run elevated:
function Set-Path ([string]$newPath, [bool]$permanent=$false, [bool]$forMachine=$false )
{
$Env:Path += ";$newPath"
$scope = if ($forMachine) { 'Machine' } else { 'User' }
if ($permanent)
{
$command = "[Environment]::SetEnvironmentVariable('PATH', $env:Path, $scope)"
Start-Process -FilePath powershell.exe -ArgumentList "-noprofile -command $Command" -Verb runas
}
}
Most answers aren't addressing UAC. This covers UAC issues.
First install PowerShell Community Extensions: choco install pscx via http://chocolatey.org/ (you may have to restart your shell environment).
Then enable pscx
Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser #allows scripts to run from the interwebs, such as pcsx
Then use Invoke-Elevated
Invoke-Elevated {Add-PathVariable $args[0] -Target Machine} -ArgumentList $MY_NEW_DIR
To be clear, the 1990's Windows way of click on Start, right click on This PC, and choose Properties, and then select Advanced system settings, and then in the dialog box that pops up, select Environment Variables, and in the list double clicking on PATH and then using the New, Edit, Move Up and Move Down all still work for changing the PATH. Power shell, and the rest of Windows get whatever you set here.
Yes you can use these new methods, but the old one still works. And at the base level all of the permanent change methods are controlled ways of editing your registry files.
Open PowerShell and run:
[Environment]::SetEnvironmentVariable("PATH", "$ENV:PATH;<path to exe>", "USER")
These scripts are idempotent (can be run more than once).
They update both the Windows path and the current / future Powershell sessions:
Permanently add path
$targetDir="c:\bin"
$oldPath = [System.Environment]::GetEnvironmentVariable("Path","Machine")
$oldPathArray=($oldPath) -split ';'
if(-Not($oldPathArray -Contains "$targetDir")) {
write-host "Adding $targetDir to Machine Path"
$newPath = "$oldPath;$targetDir" -replace ';+', ';'
[System.Environment]::SetEnvironmentVariable("Path",$newPath,"Machine")
$env:Path = [System.Environment]::GetEnvironmentVariable("Path","User"),[System.Environment]::GetEnvironmentVariable("Path","Machine") -join ";"
}
write-host "Windows paths:"
($env:Path).Replace(';',"`n")
Permanently remove path
$targetDir="c:\bin"
$oldPath = [System.Environment]::GetEnvironmentVariable("Path","Machine")
$oldPathArray=($oldPath) -split ';'
if($oldPathArray -Contains "$targetDir") {
write-host "Removing $targetDir from Machine path"
$newPathArray = $oldPathArray | Where-Object { $_ –ne "$targetDir" }
$newPath = $newPathArray -join ";"
[System.Environment]::SetEnvironmentVariable("Path",$newPath,"Machine")
$env:Path = [System.Environment]::GetEnvironmentVariable("Path","User"),[System.Environment]::GetEnvironmentVariable("Path","Machine") -join ";"
}
write-host "Windows paths:"
($env:Path).Replace(';',"`n")
The simplest solution that I found to add C:\vcpkg permanently to my PATH env variable without drawbacks was :
$current_PATH = [Environment]::GetEnvironmentVariable("PATH", "USER");[Environment]::SetEnvironmentVariable("PATH", "$current_PATH;C:\vcpkg;", "USER")
You can change "USER" to "MACHINE" to change system env vars (need an admin terminal and you may need to change Environment to System.Environment) or even to "PROCESS" to only change local PATH env var (not permanently changed). Respectively "USER"=1 "MACHINE"=2 and "PROCESS"=0 here are the documentation about those commands: GetEnvironmentVariable SetEnvironmentVariable
Two other answers that I found but have major drawbacks and I do not recommend to use them. Both use SETX as it is implemented by PowerShell to change permanently env variable. The down side of those commandes are that you will duplicate your system PATH into your locale PATH and you need PowerShell to use them:
setx PATH "$($Env:PATH);C:\vcpkg;"
Longer but allow an usage with other env variable:
$($Env:PATH).Split(';') | %{ $str += "$($_.Trim('"'));" }; %{ $str += "C:\vcpkg;" } ; setx PATH $str; %{ $str = "" }
I tried to optimise SBF's and Michael's code a bit to make it more compact.
I am relying on PowerShell's type coercion where it automatically converts strings to enum values, so I didn't define the lookup dictionary.
I also pulled out the block that adds the new path to the list based on a condition, so that work is done once and stored in a variable for re-use.
It is then applied permanently or just to the Session depending on the $PathContainer parameter.
We can put the block of code in a function or a ps1 file that we call directly from the command prompt. I went with DevEnvAddPath.ps1.
param(
[Parameter(Position=0,Mandatory=$true)][String]$PathChange,
[ValidateSet('Machine', 'User', 'Session')]
[Parameter(Position=1,Mandatory=$false)][String]$PathContainer='Session',
[Parameter(Position=2,Mandatory=$false)][Boolean]$PathPrepend=$false
)
[String]$ConstructedEnvPath = switch ($PathContainer) { "Session"{${env:Path};} default{[Environment]::GetEnvironmentVariable('Path', $containerType);} };
$PathPersisted = $ConstructedEnvPath -split ';';
if ($PathPersisted -notcontains $PathChange) {
$PathPersisted = $(switch ($PathPrepend) { $true{,$PathChange + $PathPersisted;} default{$PathPersisted + $PathChange;} }) | Where-Object { $_ };
$ConstructedEnvPath = $PathPersisted -join ";";
}
if ($PathContainer -ne 'Session')
{
# Save permanently to Machine, User
[Environment]::SetEnvironmentVariable("Path", $ConstructedEnvPath, $PathContainer);
}
# Update the current session
${env:Path} = $ConstructedEnvPath;
I do something similar for a DevEnvRemovePath.ps1.
param(
[Parameter(Position=0,Mandatory=$true)][String]$PathChange,
[ValidateSet('Machine', 'User', 'Session')]
[Parameter(Position=1,Mandatory=$false)][String]$PathContainer='Session'
)
[String]$ConstructedEnvPath = switch ($PathContainer) { "Session"{${env:Path};} default{[Environment]::GetEnvironmentVariable('Path', $containerType);} };
$PathPersisted = $ConstructedEnvPath -split ';';
if ($PathPersisted -contains $PathChange) {
$PathPersisted = $PathPersisted | Where-Object { $_ -ne $PathChange };
$ConstructedEnvPath = $PathPersisted -join ";";
}
if ($PathContainer -ne 'Session')
{
# Save permanently to Machine, User
[Environment]::SetEnvironmentVariable("Path", $ConstructedEnvPath, $PathContainer);
}
# Update the current session
${env:Path} = $ConstructedEnvPath;
So far, they seem to work.
Lots of examples of appending, or overwriting. Here is an example of prepending a path on powershell for Linux, Ubuntu 18.04 with pwsh 7.1.3
$ENV:PATH = "/home/linuxbrew/.linuxbrew/bin:$ENV:PATH"
I'm specifically adding the linuxbrew (homebrew for linux) bin directory to take precedence over the system installed. It helped solve an issue I was having and although this was the most helpful place, it also left me "experimenting".
Note that the : is Linux path separator, whereas on Windows (or at least my windows) you would use ; for powershell typically.
Editing the registry key in #ali Darabi's answer worked best for me, but
When I didn't have the right permissions to do it from Powershell. So I edited it directly in regedit.
I want to expand further on the subject in this answer.
Restarting Powershell also wasn't sufficient to propagate the change. I had to Open Task Manager and restart explorer.exe to trigger a reload of the registry.
It can be quite tedious to navigate the registry so in order to maintain an user friendly experience you can execute this from Powershell:
REG ADD "HKCU\Software\Microsoft\Windows\CurrentVersion\Applets\Regedit" /v "LastKey" /d "HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment" /f; regedit
It sets the last opened window to a certain registry path, so that when you open regedit the next time it opens at the proper key.
If you need to set variable name dynamically and for session only, then use:
New-Item env:\$key -Value $value -Force | Out-Null

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