Somehow Visual Studio search has stopped working for me. Anytime I search \"Entire Solution\" for some text I get this result:
Find all \"[Whatever I
Ctrl+Break or Ctrl+ScrLk cancel a find operation. Try it. What has happened is that some software layer (presumably Windows) thinks those keys are still being pressed even though they are not. Pressing and releasing them clears the flag.
It could be any of these combinations:
Ctrl+Break
Alt+Break
Break
Ctrl+ScrLk
Remember that you have multiple control and alt keys on your keyboard -- try it with each of them. If it's the right Ctrl key + ScrLk, pressing the left Ctrl is not going to resolve the issue.
Here is the Connect issue which Microsoft closed as "Won't Fix".
If this is a recurring problem for you, there is a Visual Studio extension that suppresses the virtual key that causes the problem.