Form errors based on multitable parameter query

[tim_tims33]

Hi,
I have built a form intended for the user to search and filter records, via use of combo boxes, in my database. The datasource for the form is a query, which employs parameter criteria (references to the values selected in the controls placed on main form). If my query datasource is one table it works fine. However, when i add an extra two tables to the query (and add extra fields accordingly) the search/filter form doesn't work. Now i'm left wondering if parameter queries only work for one table? Please help me out if you can!
Many thanks.

 

[jdraw]

Please show the query involved, and any form event code if it exists.

 

[tim_tims33]

Attached is are two files. A screen dump of the form (in design view) and a screen dump of the query (in design view). I hope this adds some clarity. Note: there is no form code...just a 'requery' macro when the user presses search. In fact, i am hoping that if a solution exists, it isn't a 'coded' solution.