Why do my windows go dark when they're on my external monitor?

Why is this happening? Has any one ever experienced anything like this before? Some windows stay dark on my external monitor and some come good after I let go of the cursor after dragging..

Screenshot Over Laptop screen and External Monitor.


Solution 1:

Check this thread out: https://discussions.apple.com/message/16608477

To quote: "...opening Display in System Settings, and choosing calibrate under Color seems to have fixed the problem." I don't have my external monitor with me at the moment, but wil check when I'm at work tomorrow.