Sony PCV-RX851 Online Help Center (VAIO User Guide) User Manual page 87

Why can't I play a DVD or CD media?

After inserting your optical disc, wait a few seconds for it to be detected before trying to access it.
 Verify 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.
To recover the CD or DVD software applications that are preinstalled on your computer, see
the online User Guide for more information.
Reinstalling software in
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