Sony PCV-RS423P - Manual (Page 108)

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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