I've compiled a dll which compacts databases given the filepath, password etc of the DB and it works just fine, however I test for an ldb using FileExists and if this returns True the dll doesn't compact but reports back to the user via a MsgBox. The report only works in the design environment when I have both the dll and the Project using the dll open in a group. If I run using the compiled dll it works but doesn't report using the MsgBox. Does MsgBox work from a dll? I can get the dll to return True or False of course but am curious as to whether a dll can use MsgBox.