Running Access on a Windows Vista peer to peer network?
Are you running Access on a Windows Vista peer to peer network? That is the back end MDB is on a Windows Vista machine. And the front end is also on a Windows Vista box. Wierd things are happening? Performance is terrible or Access crashes? The problem is Server Message Block 2.0 (SMB). (This sounds somewhat similar to the OpLocks corruption problem a number of years ago.)
Then you need to either use a Windows XP or other system as the server or get the recently released hotfix. See the KB article Issues that you may encounter when you open or are using a Microsoft Office Access database on a computer that is running Windows Vista
You're running the database on Windows Longhorn Server? On a beta operating system? You're much braver than I am. However that same article applies.