Question

I’m receiving this error when trying to see a report.

Answer 1

Well if this happened to you, you’ve probably has just changed the password of the user that runs the Reporting Services.

You probably can’t access the Report Manager either.

Scenario:

Windows 2003 Server /
Reporting Services 2008

The way I fixed this was the following:

1. Open a console (cmd)
2. Typed in this: rskeymgmt -d
3. Press Y and hit enter.
4. Now you have access to the report manager.
5. Go to the Data Source Properties and review your data sources: in my case i just fixed one data source (so take in advice this fix if you have plenty data sources). In my case I set that use the credentials: user and password for the user that runs the reports.
6. That’s it.

Source:
This page helped me

Hope it helps