CP wrote:
I have compacted an mdb which had user and group permissions
associated with it. After compacting however, I was locked out of the
original databse and the compacted copy. The message was "You do not
have the necessary permissions to use the ...FileX...object. Have
your system administrator or the person who created this object
establish the appropriate permissions for you.

The compacting process did not reset the permissions. You are not using the
correct workgroup file to open the mdb.

You likely are joined by default to the standard system.mdw, while your
secure database needs to use the workgroup file you secured it with in order
to authenticate the users.

Try creating a desktop shortcut to launch the secure mdb. The target would
look like:
"path to msaccess.exe" "path to mdb" /wrkgrp "path to secure.mdw"

--
Joan Wild
Microsoft Access MVP