They must have Change permission (Read, Write, eXecute and Delete) on the
folder where the MDB exists.
This is because the first user into the database creates a locking file
(.ldb) in the folder, subsequent users update that file, and the last user
out of the database deletes it.

Signature
Doug Steele, Microsoft Access MVP
http://I.Am/DougSteele
(no e-mails, please!)
> Windows XP / Access 2002
>
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>
> Bob