Did you install Cumulative update package 5 for SQL Server 2008 R2 Service Pack 1 854094 2644260 FIX: A main report is re-rendered when you click a link to view a drillthrough report in SSRS 2008 R2 Check this article: FIX: A main report is re-rendered when you click a link to view a drillthrough report in SSRS 2008 R2

Thanks, put on CU5 but it had no effect. Our symptoms don't match the symptoms in the article you quoted. We don't get any re-rendering - as soon as the hyperlink is clicked, the reportviewer control displays the object reference error, which no doubt means it can't find the subreport itself, in spite of the full .rdl name being specified for the Action item. This is very disappointing. Seems like such a simple thing to get right. thanks again, r

Experiencing a problem with drillthrough's in .rdl files after applying some SP1 patches, so would appreciate any advice. Here's what happened: After applying SP1 for Visual Studio 2010, the intellisense in SQL Server Management Studio (2008 R2) stopped working. So applied the SP1 for SQL Server 2008 R2 and that fixed the intellisense, but it broke the report drillthru in .rdl's in the Visual Studio 2008 R2 preview pane (which is the version we're using for .rdl report development). So applied the hotfix that fixes the report drill through capability in VS2010 (which also breaks apparently) hoping it would fix the 2008 drillthru prob. but it had no effect on the drill through in VS2008. Error is 'Object reference not set to instance of an object'. Here's a map of what we've discovered. VS2010 | SQL 2008 R2 | SSMS Intellisense | VS2008 Drillthru ------------|--------------------|--------------------------|------------------ - | - | Ok | Ok ------------|--------------------|--------------------------|------------------ SP1 | - | Broken | Ok ------------|--------------------|--------------------------|------------------ SP1 | SP1 | Ok | Broken ------------|-------------------|---------------------------|------------------ So while the hotfix may well fix the drillthrough in VS2010, VS2008 seems to have been forgotten. Does anyone know how to fix the drill through in Visual Studio 2008 R2 SSRS preview pane after these SP1's are installed? We did find one workaround. In the hyperlink Action item where the target report is specified, if we drop the ".rdl" from the report name then the drillthrough works in the preview pane. But if this same report is then migrated to our Sharepoint reporting portal, the drillthrough fails. Put the ".rdl" back in, then local preview fails on drillthrough, but Sharepoint drillthrough works! Any advice appreciated. tia r