Can't find assemblies specified

Question

I'm on CRM 4.0 and I get the following error when I try to execute retrieval of multiple entities.

Could not load file or assembly 'System.Core, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' or one of its dependencies. The system cannot find the file specified.

I'm pretty sure that the assembly referred is microsoft.crm.sdktypeproxy because the other one (microsoft.crm.sdk) is doesn't create any issues.

So I went to the server and added the former at each location where the latter resides. To no avail. I need the assembly because I'll be retrieving multiples instances of custom entities.

I copied the DLLs to CRMWeb\bin and Server\bin as well as my plugin registration tool directory and in IIS at a few places. How can I trouble-shoot this one?!

Answer 1

The error refers to a .NET 4.0 assembly, probably your Dynamics CRM 4.0 environment has not been updated to (at least) rollup 18, the minimum rollup that support .NET 4.0, as stated here:

Microsoft Dynamics CRM Compatibility List

If the CRM has a lower rollup it supports only .NET 3.0/.NET 3.5

Answer 2

The tool to use for troubleshooting is fuslogvw. If any of the assemblies referenced are native 32bit or 64bit, make sure your application is set to match - that is a common cause of this exception.