This issue was caused by a Visual Studio 2008 to Visual Studio 2010 conversion error. In the original solution, there was a project that had a broken reference. This reference was a project that was long ago removed, but apparently no errors/warnings were given in MSVC 08. When converting the project to MSVC 10, this broken reference was converted as well. Since the reference was broken, the path to the reference project was set as the project identifier, hence why I was only seeing the project identifier in the warning message.
To fix this, I had to edit the .vcxproj project file and manually remove the broken reference. You can't fix this through Visual Studio because the converted project will never show the broken project as a reference.
Finding it in the .vcxproj file is easy, just search for the project identifier (in this case 5BED5853-86EB-BA4F-A6E2-25A211A18E33) and remove the entire <ProjectReference>
tag referring to it.