Shift+C no longer working I am not sure why and quite saddened by this but I can no longer type a capital 'C' on my keyboard for my Mac mini running OS X Yosemite. I have run through all of the shortcuts in System Preferences->Keyboard->Shortcuts, but Shift+C is not listed there, anywhere...

What is causing this, and how to fix it?
Have you taken that keyboard to another computer or tried another keyboard on the Mac Mini? 

The most elegant solution to your problem would be if it's a hardware issue on that specific keyboard.