>Why is it when I try to check out a DATABASE i get the error message: Source cannot operate on an open file, close the file and try again.
>
>I do not have this file open!!!

Are you sure? If you open any table contained in the DBC, the DBC is automatically open. It may not be active (i.e. SET('DATABASE') returns null string) but it open just the same.

Using CLOSE DATABASES without activating the database doesn't do anything. CLOSE DATABASES ALL will close the database even if not active.

HTH.