Mixed mode assembly is built against version 'v2.0.50727' of the runtime and cannot be loaded in the 4.0 runtime without additional configuration information. in Visual studio and crystal report 2012

Hello

I am having following issue with Visual Studio 2012 run time and Crystal reports. I have download and installed Crystal reports and Run time environment from URL http://scn.sap.com/docs/DOC-7824 and version Support pack 12 v.13.0.12.1494 but it is showing me following error 

Mixed mode assembly is built against version 'v2.0.50727' of the runtime and cannot be loaded in the 4.0 runtime without additional configuration information.

Please help me and tell what should i do now.

sajid

Sajid Manzoor