It's caused by various cd/dvd recording software. The fix is turning out to be the safe as XP. Typing CODE 39 REMOVE UPPERFILTERS LOWERFILTERS at google.com finds the articles of interest.
Bob
Please help. My daughter has an Acer Aspire 5100 Vista that is only about one month old. Just tried putting in one of her school videos and now the computer is not recognizing the CD/DVD drive. I've looked under My Computer and all it shows is the "C" Drive and the "D" Drive. We have not downloaded any music software. Please help as we have to use this drive for her school CDs. Access to the internet is very limited and we have anti-virus (Norton) Webroot Spyware and a filter on this computer. Thanks

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