could not load file or assembly 'system.core version=2.0.5.0

Question

I was trying to use ReactiveUI in a WPF application that makes use of Prism. I installed the packages with NuGet, but simply adding the references led to the exception specified in the title during the initialization of the ModuleCatalog.

Edit:

As Pierre Arnaud pointed out, the problem is Microsoft.Bcl.Async not being able to resolve System.Core version 2.0.5.0.

We moved to Visual Studio 2012 since i first posted this question. The same problem persists and i can't even install the fix suggested by Pierre since i have installed .Net 4.5 now. The project is still targeting .Net 4.0.

Answer 1

Please install KB2468871, which solves the issue related to Microsoft.Bcl.Async not being able to resolve System.Core version 2.0.5.0.

See also Issue 8 in the async targeting pack knowledge base.

Here are the direct download links for the fixes, for the x86 and x64 environments:

• http://download.microsoft.com/download/2/B/F/2BF4D7D1-E781-4EE0-9E4F-FDD44A2F8934/NDP40-KB2468871-v2-x86.exe
• http://download.microsoft.com/download/2/B/F/2BF4D7D1-E781-4EE0-9E4F-FDD44A2F8934/NDP40-KB2468871-v2-x64.exe