I just spent about 2 hours pulling my hair out over this issue, and I
don't want it to happen to anyone else ever again. Ever.
Basically you try to close a form using "DoCmd.Close", the form has a
parameter query somewhere on it (for me it was in a couple of combo
boxes), and you _sometimes_ get a dialog box asking you for the
parameter. If you've worked with parameter queries before you know the
box I'm talking about.
Here's the MS info on it:
http://support.microsoft.com/kb/811860/en-us
To fix you can use one of the MS workarounds or you can put a
"DoCmd.Restore" in the Close event of the form. Also this might be
fixed in Access 2003 but I'm not sure.
Jon LaRosa