I have a session host group that uses user profile disks. When I try to login a second time into the group with a user account, I expect that the user should get logged in with a temporary profile due to the other session locking the UPD. Instead, the user profile service is failing the login due to the inaccessible profile. On my previous domain, this wasn't an issue.
I checked and verified the obvious GPO setting, "Do not log users on with a temporary profile" was NOT enabled. I'm not sure what else could prevent the temporary profile from being created.