Report Builder: Filter drop down list unspecified

I have a report model which functioned correctly until I copied the project
over to another server and changed the data source for it. I can still build
a report that returns the correct data, but when I add a filter to the report
data, the ddl for the filter never loads the data and says 'unspecified'.
I'm not sure what the problem could be. Any ideas? ThanksAfter doing some hunting around I found this:
One of the most commonly used features in ad-hoc reporting is filtering. To
add filters to a report, select a field, and then click the Filter button. If
the InstanceSelection attribute enables drop-down, filter values will be
automatically populated. In article
http://msdn2.microsoft.com/en-us/library/aa964121.aspx#adhocrptsol_topic5
This is not the issue asthe InstanceSelection property is properly configured.
"Jason" wrote:
> I have a report model which functioned correctly until I copied the project
> over to another server and changed the data source for it. I can still build
> a report that returns the correct data, but when I add a filter to the report
> data, the ddl for the filter never loads the data and says 'unspecified'.
> I'm not sure what the problem could be. Any ideas? Thanks