How to find AD group membership with PowerShell

A tiny snippet I always forget when swapping identities and using service accounts for things like IIS App Pools. The problem: given a user name how do I work out which AD groups they belong to?

Activate Active Directory

First, we need to make sure that the ActiveDirectory module is available. On Windows 10, this is a capability:

Add-WindowsCapability -Name Rsat.ActiveDirectory.DS-LDS.Tools```~0.0.1.0 -Online

Confusingly, for Windows Server OS' it's a windows feature:

Install-WindowsFeature -Name "RSAT-AD-PowerShell" -IncludeAllSubFeature

Which Groups Am I In?

Import-Module ActiveDirectory

Get-ADPrincipalGroupMembership MyUser.Name | select name

Piping to Select name strips away the cruft we generally don't care about and gives us a nice list of the groups.

Who Is In This Group?

The other side of this problem is looking at a group and getting the members of that group.

Import-Module ActiveDirectory

Get-ADGroupMember -Identity "MyADGroupName"