NT 4 SP6 Logon getting corrupted

Have some users on a small NT4 lan setup to logon with scripts etc

The users who dont log on very often, or just use the NT4 Workstations for mail etc have no problems

The power users who are on all the time seem to have there identity corrupted and programs that ran before, office etc, stop working and keep wanting reinstallation – eventually it becomes so bad I just have to create a new account and then everything is fine for a while

The workstations only have 64MB and at first as the profile kept asking if you wanted to revert to the local one or download I thought the machines had been locking up and the profile had lost its way

any ideas

pete