Issue:
An unhandled exception of type 'System.IO.FileNotFoundException' occurred in mscorlib.dll
Additional information: Could not load file or assembly 'file:///C:\Program Files (x86)\SAP BusinessObjects\Crystal Reports for .NET Framework 4.0\Common\SAP BusinessObjects Enterprise XI 4.0\win32_x86\dotnet1\crdb_adoplus.dll' or one of its dependencies. The system cannot find the file specified.
Solution:
Simply add useLegacyV2RuntimeActivationPolicy="true" in startup tag in app.config file.
example: <startup useLegacyV2RuntimeActivationPolicy="true">
