You can load workbooks each time when excel starts via the Tools|Addins dialog.

If you've moved/deleted one of those files, excel will yell at you that it can't
find it.

If you start excel (ignore the message) and then
tools|addins
you can uncheck the selected addins. When you uncheck the missing addin, excel
will notice that it can't find it and ask if you want to remove it from the
list.

(Remember to recheck the addins you want loaded.)

Chip Pearson has some notes on how to diagnose startup errors at:
http://www.cpearson.com/excel/StartupErrors.htm

You may want to bookmark this for future reference.

roadkill wrote:

What would cause a "file not found" error upon starting Excel (w/o any
reference to a file to be loaded on startup). I've checked in the VBA screen
and can find no macros set to fire on startup.

--

Dave Peterson