Please bear with me, this is quite a specific issue which I'll try and detail as best I can.
I've inherited a couple of Visual Studio projects, one of which references another. In a class in a project called TCG.Toolkit there is a reference to a class called The1440.Classes.Designer.
This project used to compile without any problems, now the Designer bit of the the using statement has a red underline and in the references section of the project there is a little yellow triangle next to the reference.
I have tried adding in the reference again but I cannot see a class called Designer in the The1440.Classes project.
I have tried changing the .NET version from 4 to 3.5 and back again as I read somewhere that this can sometimes cause the problem.
Please let me know what other information you may need to solve this problem.