Find if a program is installed on remote computer - windows

Question

I am trying to connect to remote computers with Active Directory and see if a single program is installed. I have tried a couple tutorials I found on the Internet, but with no success:
http://windowsitpro.com/powershell/what-applications-are-installed-computers-your-network
http://community.spiceworks.com/scripts/show/2170-get-a-list-of-installed-software-from-a-remote-computer-fast-as-lightning
I cannot get them to work properly, and they are not exactly what I am looking for.
An example of what I want to do: say I have 3 computers on my network:
123-abc
123-bcd
123-cde
and I want to see if the executable C:\Program Files (x86)\Mozilla Firefox\Firefox.exe exists. Can someone please explain how I can go about this in PowerShell?

Answer 1

The simplest way, provided you have domain admin privileges and administrative shares are enabled and accessible on the target computers, would be this:
$computers = '123-abc', '123-bcd', '123-cde'
$path = 'C$\Program Files (x86)\Mozilla Firefox\Firefox.exe'
$computers | % {
'{0}: {1}' -f $_, (Test-Path -LiteralPath "\\$_\$path")
}

Answer 2

There are a handful of ways to check for installed software. Some better suited than others. But if you're certain on the file path on each machine, the Test-Path CmdLet could be an easy approach.
Invoke-Command -ComputerName 123-abc -ScriptBlock {Test-Path 'C:\Program Files (x86)\Mozilla Firefox\Firefox.exe'}
You could probably throw that into a loop with a custom object so you can work with it as well.

Answer 3

For example, your code could look like this.
$pass = "password";
$secpass = ConvertTo-SecureString $pass -AsPlainText -Force;
$creds = New-Object System.Management.Automation.PSCredential("domain\login", $secpass);
Invoke-Command -ComputerName 123-abc, 123-bcd, 123-cde -Credential $creds -ScriptBlock {
Test-Path "C:\Program Files (x86)\Mozilla Firefox\Firefox.exe"
};
There are multiple ways of running powershell commands on remote computers.
Many commands support string[] parameter -ComputerName to which you can pass multiple computer names
You can use the Enter-PSSession cmdlet to enter a Telnet-like session on the remote machine
And finally, you can use the Invoke-Command cmdlet to run a script block against multiple remote hosts.