>I recently made some major changes to a project I was working on - including removing some tables and adding some new ones. I went to into the database designer to remove some of the old tables and edit the referential integrety. I got a message saying that I need to run "Clean up Database" from the Database menu. Only problem is, its greyed out. Any ideas?

The database container might be open shared instead of exclusive. Do
CLOSE ALL
SET EXCLUSIVE ON
OPEN DATABASE myDatabase