Visual Studio 2010 has an annoying tendency to somehow lose references to DLLs — the reference worked for ages and out of the blue you receive a warning: The referenced component ‘Xyz’ could not be found.
If you have the source for the DLL there’s an easy workaround:
- Reference the project that creates the DLL
- Reference the DLL from the Add Reference window’s Projects tab
Additional goodies: all the DLL’s TODOs show up in your Task List, no more stale references and the Go To Definition command showing the code and not just the interface.