Help with Access XP Error 2001 "You canceled the previous operation"

[RWC]

Hi,

I'm running into a problem with Access XP (SP2) that's driving me up the
wall. It's Error 2001 "You canceled the previous operation". There is no
voodoo going on really when I get this message. The following Dlookup field
is causing this message. All field data types are correct.

DLookup("tDescription", "RelatedTable", "iIntegerField = " &
(DLookup("iIntegerField", "TableOne")))

I hit the "Help" button and got a big grey screen where the help text should
be.

Any help ANYONE can give would be greatly appreciated. Just remove the caps
and underscores from my email address when replying to this message.

Thanks!
RWC