Our solution has several projects(like over 100), most of which work fine. However anytime a markup file from the "main" project(which the rest of them build into) is open and we attempt to build or debug we get the following:
Error 18 Value of type 'System.Collections.Generic.List(Of IInterface)' cannot be converted to 'System.Collections.Generic.List(Of IInterface)'. Type mismatch could be due to the mixing of a file reference with a project reference to assembly 'OurAssembly'. Try replacing the file reference to 'OurAssembly.dll' in project '1_ASPPageLoader.ascx' with a project reference to 'OurAssembly'.
There are 3 errors like this, all coming from another project. As soon as you close the markup file the build works great. I obviously tried to do what the message said, but there is no reference to either the .dll or project whatsoever.
The 2 project files in question look normal, but I could be missing something. Any help/direction is appreciated!