It was just showing as a SID instead of the username. There was another instance where the Session host was also the file server, but since the DNS was changed, the system couldn't resolve who were the users that were set on the permissions for the UPD. We've seen cases where the DNS settings were changed, therefore the Session server wasn't able to find the File server to grab the UPD's. Click here for step by step instructions on how to clear out the back up and temp profile from the registry. Sometimes when a user's profile is locked, the system makes a back up of it, then creates a temp profile for the user to log in with. To be able to identify which disk belongs to what user, you can use Microsoft's SIDDER application.

Go through the disks and verify that the permissions are set, and that the user is assigned to the disk. The disks are stored on the File server in the root of the data disk in a folder called 'Profile'. If the UPD has the wrong permissions it could also say access denied. If the UPD is mounted or missing, the logs will tell you it can't be found. To solve the issue follow the below steps:

Verify disk could not unmount disk