Sony PCV-W20 Manual
Why can't I play a DVD or CD media?
After inserting your CD or DVD, wait a few seconds for the system to detect it before trying to access it.
Confirm that the disc is in the tray with the label side facing up.
Install your CD or DVD software according to the manufacturer's instructions.
If your drive reads some DVDs or CDs, but not others, check the shiny side of the disc for dirt or scratches.
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more information.
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