Word, Excel locking up on NT Domain

Our hospital has been having problems with Word and Excel locking up with no error messages,on an NT domain. Problem occurrs only with Office 2000, and only on Dell PC’s. Similar Dell’s only on Novel server have no problems but once moved to NT problem begins. Neither Dell nor Microsoft have come up with any solutions. If the Dells are formatted and all programs reinstalled, they work fine but this is time consuming. Any suggestions to eliminate reformatting PC’s would be greatly appreciated.