"Ambiguous reference" after build/compilation

I get lots of 'ambiguous reference' errors after building my web application (sounds like http://stackoverflow.com/questions/191950/how-to-resolve-incorrect-ambiguous-reference-from-resharper-on-class-inheritanc)

I believe it's caused by R# including DLLs in the application's bin folder, even if they're not referenced in the project, and it then finds an ambiguity between the project code and the compiled DLL in the bin folder. When I delete the DLL the errors disappear.

Is this a bug, by design or is there something fundamentally wrong with the setup of my web application?


Jakob Donkersloot

using:
VS 2010
R# 5.0.1659.36 (demo)