Access 2007 ApplyFilter

I have a problem with Access databases created in Access 2000 but now using Access 2007

I have a combo box on a form listing all people a filter is applied to the data on the form when a person is selected from the box. The Event AfterUpdate uses the code DoCmd.ApplyFilter , “[MemberId] = Forms!frmMembers!FindMember” to show the selected person.

This works fine once (and has always worked in previous versions of Access) but if you select another person their details are not displayed. Closing the form and reopening the filter works once and then doesn’t display the seconf selection. Any ideas?