WCF Service Reference Error

I tried updating my WCF service references in my web project and received this strange error:

Error        265          Missing partial modifier on declaration of type 'xyz'; another partial declaration of this type exists   Reference.cs

This mean't I had a class in the service or the web projects that are named the same but are not set as partials. The problem was in the service project the complex object in my EF 4 entities did not generate a partial class when referenced in the References.cs file of the web project.

I had to configure the service reference to reuse the System assembly, then update my reference again and everything worked - strange error :(

This post helped me a bit http://stackoverflow.com/questions/8542514/wcf-reference-cs-suddenly-not-including-classes