This error message comes up when trying to view parent report that has a group and details (expandable from the group). It works fine on a 2005 server. Another report without grouping shows ok on 2008.. All developped in VS2005. table1 is not a name used anywhere in the report, must refer to something internal. Error: An error occurred during client rendering. An error has occurred during report processing. The processing of Parent for the tablix table1 cannot be performed. The comparison failed. Please check the data type returned by the Parent. The processing of Parent for the tablix table1 cannot be performed. The comparison failed. Please check the data type returned by the Parent.

Hi Alokazia, If all of your other reports are working normal, this looksto bea product bug specific to that report. Please file a bug report at http://connect.microsoft.com. Include the report server log files, repro steps,and a generic RDL and generic dataif possible.

Brad, could you instruct me how to file a bug report at http://connect.microsoft.com. I have registered on that site. Thank you

I posted the bug report https://connect.microsoft.com/SQLServer/feedback/ViewFeedback.aspx?FeedbackID=367275 Morequestions on SSRS: how to open an SSRS project in VS2008? The reports do not show up. How to load report parameters values from a Sproc in VS2008?? It was available in VS2005. Thank you

SSRS report projects only come with the BI Development studio. Do you have the new BI Development studio for RS 2008 installed with your VS 2008 installation? VS2008 does havethe newReport Projects that use the Report Viewer control. But that is not the same as an RS Report Project. Parameters functionality should be the same. In the query designer, make sure your command type is set to Stored Procedure.

Reason for above error can be Praent group and child group are having different DataType ... While making Parent-Child grouping on tables please make sure that u r using same data type for both the columns used in grouping ... . Let me know if its works .... Thanks.. UT