I just installed mdac 2.1 on an NT Server with SP6. Now none of the Access db&#039s can be researched. I have reinstalled mdac 2.1 and SP6 still no good. Here&#039s the message "[Microsoft][ODBC Microsoft Access Driver] The Microsoft Jet database engine cannot open the file &#039(unknown)&#039. It is already opened exclusively by another user, or you need permission to view its data. " I have gone back and recreated the DSN for the access database (It&#039s Access 97). There doesn&#039t seem to be any easy way to roll back the upgrade. Has anyone had similar problems.<BR><BR><BR>