DVD Burner is locked - How do I test to find the problem software

I am able to burn CDs, however none of my various burning software can burn a DVD because there is an error message saying that the drive is locked. How do I test to find the software or application that is causing this problem?

This is a brand new problem that occurred since I added DVD Decrypter and ImgBurn. I have now removed those apps, but still having the problem. I am blowing through blank discs trying to troubleshoot.

Please help…