Hi, I have a Casio CTK 2080 keyboard, and Samplitude Music studio MX.. umm the 2011 version I guess, and I am using Windows 7. whenever I try to use it to record, an error message will pop up that says...

 Can't open MIDI device:

CASIO USB-MIDI (IN Port #1)

The device is probably used by another application

 But I have no idea what that other application would be. I am new to this whole beatmaking software idea, so I would greatly appreciate some help. thank you!!!