Thanks for the reply Bob, but I fixed the problem. I uninstalled some software I had on this computer. I had several programs that may have been the culprit. (I think CloneCD was the only one that may have been running at startup.) The mystery is that nothing new was installed and Microstudio ran fine before I installed this Plextor drive. But at least I am back in business now. I don't have any burn software on this computer now.
Thanks again,
Wally
