Launching multiple RDP sessions via powershell script - windows

Question

Here is the script:
$compnames = import-csv "$env:userprofile\Documents\list.csv"
$User = "username"
$Password = "password"
foreach ($computer in $compnames) {
cmdkey /generic:TERMSRV/$($computer.compname) /user:$User /pass:$Password
mstsc /v:$($computer.compname)
}
When I run the script, I get the following error:
cmdkey : The term 'cmdkey' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again. At C:\Program Files\WindowsPowerShell\Modules\rdpsession\1.0.2\RdpSession.psm1:92 char:1
+ cmdkey /generic:Termsrv/$computer /user:$Username /pass:$rdp > $null
+ ~~~~~~
+ CategoryInfo : ObjectNotFound: (cmdkey:String) [], CommandNotFoundException
+ FullyQualifiedErrorId : CommandNotFoundException
mstsc : The term 'mstsc' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again. At C:\Program Files\WindowsPowerShell\Modules\rdpsession\1.0.2\RdpSession.psm1:94 char:1
+ mstsc /v:$computer
+ ~~~~~
+ CategoryInfo : ObjectNotFound: (mstsc:String) [], CommandNotFoundException
+ FullyQualifiedErrorId : CommandNotFoundException
It seems like powershell doesn't recognize cmdkey and mstsc. I've tried googling for hours with no solution. Hoping some one knows what the issue is here preventing the script from running.
Thanks!

Answer 1

Make sure that the actual executables are in your path.
e.g.
dir "$($env:systemroot)\system32\cmdkey.exe"
dir "$($env:systemroot)\system32\mstsc.exe"

Answer 2

The errors are specif.
cmdkey : The term 'cmdkey' is not recognized as the name of a cmdlet
mstsc : The term 'mstsc' is not recognized as the name of a cmdlet
Those two items are external executables of the Windows and ran via cmd.exe, not PowerShell. Running executables/external commands in PowerShell is a well-documented thing, directly from Microsoft.
PowerShell only runs, '.ps' files. Executables are executed via cmd.exe, even from a PowerShell script, which will call cmd.exe under the covers to run them.
If you want to see your call stack of your command, that is why the Trace-Command cmdlet exists.
# Get specifics for a module, cmdlet, or function
(Get-Command -Name Trace-Command).Parameters
(Get-Command -Name Trace-Command).Parameters.Keys
Get-help -Name Trace-Command -Examples
Get-help -Name Trace-Command -Full
Get-help -Name Trace-Command -Online
PowerShell: Running Executables
https://social.technet.microsoft.com/wiki/contents/articles/7703.powershell-running-executables.aspx
As is PowerShell command precedence.
about_Command_Precedence
https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_command_precedence?view=powershell-7
1 - Alias
2 - Function
3 - Cmdlet
4 - External executable files (programs and non-PowerShell scripts)
With your use case, the call operator is most prudent.
The Call Operator &
Why: Used to treat a string as a SINGLE command. Useful for dealing with spaces.
In PowerShell V2.0, if you are running 7z.exe (7-Zip.exe) or another command that starts with a number, you have to use the command invocation operator &.
The PowerShell V3.0 parser does it now smarter, in this case, you don’t need the & anymore. >
Details: Runs a command, script, or script block. The call operator, also known as the "invocation operator," lets you run commands that are stored in variables and represented by strings. Because the call operator does not parse the command, it cannot interpret command parameters
Example:
& 'C:\Program Files\Windows Media Player\wmplayer.exe' "c:\videos\my home video.avi" /fullscreen
Things can get tricky when an external command has a lot of parameters or there are spaces in the arguments or paths!
With spaces, you have to nest Quotation marks and the result is not always clear!
In this case it is better to separate everything like so:
$CMD = 'SuperApp.exe'
$arg1 = 'filename1'
$arg2 = '-someswitch'
$arg3 = 'C:\documents and settings\user\desktop\some other file.txt'
$arg4 = '-yetanotherswitch'
& $CMD $arg1 $arg2 $arg3 $arg4
or same like that:
$AllArgs = #('filename1', '-someswitch', 'C:\documents and settings\user\desktop\some other file.txt', '-yetanotherswitch')
& 'SuperApp.exe' $AllArgs
If the executable is not in your System path, or $env:PSModulePath, then you must provide the full path to the executable, as noted by the answer provided by 'Dan'.