User can't be deleted because it has granted/denied permissions on objects

How to determine what it has granted/denied? I've been tasked with
restoring a 3rd parties database and we're cleaning up some things including
the plethora of sql login/users and going to all domain based groups. I
cannot delete this one user. I've transferred all objects owned by it to
another user but still get this message.

I'm stuck..
Thanks for any insight here!


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