Please double-check the deployed configuration and make sure all assemblies are in the Bin folder and the application references them from that Bin folder - Deploying Web Applications
In case your web application is running out-proc session state configuration, take a look at the Design Considerations for Out-proc Session State
Also if you use report parameters in code, their actual running values can be obtained from the processing equivalent of the report as illustrated in the Using Report Events
If you need further help, please open a support ticket and send us a sample project reproducing the issue.
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