How to resolve incorrect "Ambiguous reference" from ReSharper on class inheritance?

For those who still have a problem with this, (I still get it from time to time) here's the steps I did to get rid of the ambiguous reference warning in ReSharper.

1. First I went to all my class libraries and made sure that all references to my other class libraries had the Copy Local property set to false.
2. In the project where I actually got the ambiguous reference warning, I went to my bin catalog and deleted all .dll and .pdb files for all the libraries that had their own project.
3. After a new build, or in my case "update reference" on the .dll files in VS, the errors from Resharper were gone.

I'm using Resharper 5.1 in Visual Studio 2008 with only a reference to the dlls I'm using which is why I had to "update reference"

I'm using VS 2012 and ReSharper 7 and sometimes I found the same behavior. These are the steps that worked for me:

1. Clean Solution
2. Close Visual Studio
3. Go to the root folder of your solution and find a folder called _ReSharper.[Name of your solution] and delete it.
4. Go back to Visual Studio, open up your solution the folder gets recreated and no more "ambiguous reference" errors after that.

I've seen this bug in ReSharper 4.1. It happens when the base class is in the App_Code directory. I don't know how to fix it; it is very annoying, but the code still compiles though.