Visual Studio “Go to definition” disabled or gray out

Question

Visual Studio\'s Go To Definition is disabled and F12 doesn\'t work. Other commands like Alt-F12 may continue working.

Answer 1

In my case due to my project is mapped with TFS so I am unable to go to definition also my project files showing read only when opening from Solution. So I have move to my root folder mapped with TFS and then right-clicked on folder > Go to properties > Attributes section was Read-Only I have unchecked it and clicked Apply. Reopen visual studio. Everything is now working fine.