My old CRM 4.0 was on a Windows 2003, 32 bit, platform with SQL Server 2005 installed. Recently, I installed CRM 4.0 on a Windows 2008 R2, 64 bit platform with SQL Server 2008. I also copied over and attached old database MSCRM, in mdf and .ldf, to the new server and installed CRM 4.0 rollup 1 - 8 on the new Windows 2008 R2 server. However, the problem came from the report. When I tried to run report in CRM Reports section, such as Quote, Order, etc, it cames with this error: Unable to cast object of type 'Microsoft.ReportingServices.ReportRendering.Calendars' to type 'System.String'. I have tried many approaches and feel like I starts to be scrambling. Any thoughts? It seems to have nothing with the Report Services, because I only run report in Reportviewer.
Below are a few links to information that might help. You'll need to ensure you take the correct steps in order for the upgrade from 32 bit to 64 bit to work as expected.