If the user with the mandatory profile receives:
The credentials supplied conflict with an existing set of credentials
you have persistent connections in the users profile (You did not use tip 518).
To resolve the problem:
1. Make sure no one is currently logged on with this profile.
2. Use Regedt32 to select the HKEY_USERS hive.
3. On the Registry menu, choose Load Hive.
4. Navigate to the NTUser.dat for this profile and click Open.
5. Enter JSI in the Key Name.
6. Navigate to HKEY_USERS\JSI\Network\UserName and empty the string.
7. Select HKEY_USERS\JSI.
8. Unload Hive from the Registry menu.