Sony PCV-RS321 - Manual (Page 134)

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.
 The preinstalled CD or DVD software may not be working properly. To recover this software, see the online guide,
VAIO Recovery Options , for more information.
To access VAIO Recovery Options , follow these steps:
1. Click Start in the Windows ® taskbar and click Help and Support .
2. From the VAIO Help And Support Center menu, click VAIO Recovery Options .
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