Cannot start WCF Web Service, because of ASPNETAdapter failure

Imaging you have a WCF Web Service which works fine. Unfortunately it can happen that following error occurs when somebody else try to start the service:

Could not load file or assembly 'Microsoft.VisualStudio.QualityTools.HostAdapters.ASPNETAdapter, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified

This error is caused by mixed development environment. That means you have build the service with .NET 4 at he x64 machine and somebody else is trying to host the service at his x86 development machine.
The solution is simple. Following picture shows configuration for both environments.

Hope this helps.