Windows 8 Stuck on Start Screen File Search

Have you tried rebuilding your Search index?

1. Open the Control Panel - probably the best way to do this for you will be [win] + [C] to open the Charms sidebar, and then select "Settings" then "Control Panel".
2. In the "Search Control Panel" field (top-right) type "search"
3. Select "Indexing Options"
4. Click the "Advanced" button
5. In the "Index Settings" tab (first tab, default) click "Rebuild".

If that doesn't work, you can probably manually delete your index data. Note that I have not tested this, so use at your own risk:

1. Repeat the above steps up to step 4.
2. Under "Index location" check the index storage directory (default is "C:\ProgramData\Microsoft").
3. Navigate to that folder and remove the "Search" folder; I would move it to a different location, not delete it outright, just in case you need to put it back.

Try those and see if either fixes your problem.

So this thread is even older now, but I think the problem I had was similar, and I eventually tried moving my mouse to the top left corner of my screen, and a frame appeared that I could click on, and then I was able to exit the screen, using whatever icon was in the top right corner of the screen. I have no idea if this would have helped the original poster, but I'm hopeful that if anyone else searches and finds this, they'll be able to try what eventually worked for me.