Most automated license key management tasks are done via a command called slmgr.
This command is actually an ancient VBScript. To read all of your license settings, for example, try this:
PS> slmgr.vbs /dlv
This opens a separate window, and displays many license activation details. Displaying the information in a dialog window is useless for PowerShell and automation, however when you try and run the VBScript via cscript.exe, this may fail:
PS> slmgr.vbs /dlv PS> cscript.exe slmgr.vbs /dlv Microsoft (R) Windows Script Host, Version 5.812 Copyright (C) Microsoft Corporation. All Rights Reserved. Script file "C:\Users\tobwe\slmgr.vbs" not found. PS>
You could change the default VBS host to cscript.exe, but a nicer way without touching global settings is this: find out the complete path for the VBScript, then run it with this absolute path. This is how you know where the VBScript is located:
PS> Get-Command slmgr.vbs | Select-Object -ExpandProperty Source C:\WINDOWS\system32\slmgr.vbs
And this code reads the information into the PowerShell console:
$Path = Get-Command slmgr.vbs | Select-Object -ExpandProperty Source $Data = cscript.exe //Nologo $Path /dlv $Data
$Data contains ugly plain text, though, and it is localized, too. This is not a very sophisticated way of getting license and activation info.
Since the slmgr.vbs script can do a lot of magic license tasks, as you can see when you open its help, let’s examine the source code in our upcoming text, and get to the information directly, bypassing the old VBScript.
PS> slmgr /?
Your learning points:
-
- Windows license management is often done via slmgr.vbs, a VBScript. When you call it with “/?”, you get help for its command parameters.
- PowerShell can call slmgr. To receive results, run it with cscript.exe, and provide the complete (absolute) path to slmgr.vbs.
- Get-Command is an easy way of finding the complete (absolute) paths of files that reside in one of the system folders (listed in $env:PATH).
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