We had same issue in our SSRS report.

The issue root cause is not clear but this shows up when you migrate 2005 reports on 2008 or above.

We were able...

Finally we got the issue resolved. It was problem with parameter lenght that being passed to

report. We got this resolved by decreasing the parameter length in our code.

Here is the response to the above questions.

1. This issue doesn't show up from report manager. I captured all the parameters via debug and ran the report with full parameters...