Then round up the usual suspects, starting with
* typo in criteria field name <- my guess
* are there valid values in both controls
* what datatypes are the fields
* how does the string look (do a debug.print sSQL, then hit ctrl+g to study)
* how do you run it
And please, do have a look at for instance faq181-2886, perhaps in perticular #14 ...
Roy-Vidar