After upgrading to SharePoint 2010 and Reporting Services 2008 (separate servers), all our web part pages that have the ReportViewer web parts in them are not working. The error we are getting is "Web Part Error:
A Web Part or Web Form Control on this Page cannot be displayed or imported. The type could not be found or it is not registered as safe." All the reports are working on the report server but not through the web parts. We used Visual Studio
2005 to create these reports and they all work in MOSS 2007 that also ran Reporting Services 2005. If we delete the web part with the error and put in the ReportViewer web part manually on the page in SharePoint 2010, the reports do work. But there
are too many reports to be doing this manually for every web part page. We already tried making changes to the Handler Mappings but it did not resolve the errors. As far as we can tell, all the DLLs are in the right places. Any help or suggestions would
be greatly appreciated. Thanks.
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