I was getting error while upgrading my application and hosting on the new server. This error comes because of mismatch of build version of different assemblies referenced into the project.The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040) Solution
The solution of this problem is to right click all the projects of the solution one by one and select Properties and change the Target framework version to the same framework version. Build them all and run your solution.
It should work fine now.