Hi guys,
I had the same issue w/my Macbook Pro after installing Maverick.
Found this on a discussion group, resolved the issue for me.
Hope it helps !
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ If you’re running Mac OS X 10.7 or later, open LaunchPad. Click Utilities, then Terminal in the page that opens.
Drag or copy — do not type — the following line into the Terminal window, then press return:
qlmanage -r
Test.
https://discussions.apple.com/message/18929526#18929526