Apply GPO to a single user

I've created many GPO's using Active Directory Sites and Services over the
years with no problems. However, I have a situation where I need to use GPO
to make a logon script run only for a single user.

I know how to apply a GPO to a OU or Group, but where do I go within Active
Directory Sites and Services on my PDC Server to only apply a logon script
to a single user or pc?


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