Access

I have modified a query which populates a sub form in my database, and now it asks me to enter a parameter value each time I open the form. The field it is searching for is hidden as a result of the modification of the query, so I don't know how to prevent the enter parameter value error.

The query tells me every time a customer on one form is linked to a service provider on another form. Customers may be linked to more than one service provider. There is then a sub form on the service provider form which details the results of the query (i.e. all of the customers linked to that particular service provider). In the first iteration of my query, if a customer was linked to multiple different service providers (say, three, for the sake of example) then the customer would appear three times on each of the service providers sub forms. It would be much more helpful if each customer only appeared on each form once (no duplicates).

I achieved the removal of duplication by modifying the query to only show unique values. This produced the desired result when I unchecked the show option in the design view for the service providers unique identifier field. The query now produces the result I am looking for.

The problem is that when I reopen the form, it asks me to enter a parameter value for the service providers unique identifier field. I understand that this error occurs when access cannot find a field in the underlying query data. In this instance, the underlying data is not shown on the form, to remove the duplicates. I cannot figure out how to remove the enter parameter value prompt from my form. Any help would be appreciated.

Dan