I keep getting an error -There is no disk in the drive.Please insert a disk into drive\Device\Harddrive5\DR5.?

I only get this error when using Windows Media Player playing content from my Hard drive, I am not playing anything via the disc player. The video does play but at the end the error message comes up and I have to hit cancel about 10 times before it clears the error. I am keen to keep WMP, any ideas on helping me solve this annoying problem, thanks.