This error is generated when a Report Viewer report is added to a .Net application and the report path is set to a deployed report.
Steps to resolve this issue:
1. Open Internet Explorer.
2. Type the following in the Address bar:
http://application-tier/Reports/Pages/Folder.aspx
You can find the name of the report server by opening Team Explorer, expanding the Reports node and viewing the properties of a report.
3. Click the Properties tab and then click New Role Assignment.
4. In Group or User Name, and add the Windows logon name for the user to be added to this group.
5. In Role, select Content Manager, and click OK.
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