Hi Joe Kahl,
Thank you for posting in the Q&A Forums.
If you are missing the Get-ADPrincipalGroupMembership cmdlet on Windows 11, it is most likely because you do not have the Remote Server Administration Tool (RSAT) installed or enabled.RSAT contains the PowerShell cmdlets needed to manage Active Directory.
In Win11, click Settings, search for Optional Features in the search bar, and click View Features in the Add Optional Features field. Search for “RSAT” in the search bar and add the desired feature.
Best regards
NeuviJ
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