The DVD player cannot read or play the inserted disc.
Follow this procedure to troubleshoot if the DVD player cannot read or play the inserted disc.
Ensure the inserted disc is compatible with the DVD player.
IMPORTANT: Consult the instruction manual of the DVD player for a list of compatible discs.
Use a soft cloth to clean the disc.
Examine the disc for any cracks or scratches that might be interfering with playback.
Attempt to play another disc.
NOTES:
If another disc plays in the DVD player, then the previous disc is faulty.
Some recordable discs may not play correctly because of the quality of the recording, the physical condition of the disc, or the characteristics of the recording device or authoring software used.
Remove the disc from the DVD player.
Turn off the DVD player.
Unplug the power cord of the DVD player from the AC outlet.
Let the DVD player remain without power for 1 minute.
Plug the power cord back into the AC outlet.
Turn on the DVD player.
Insert the disc into the DVD player.
Attempt to play the disc.
http://esupport.sony.com/perl/model-faq.pl?mdl=DVPNS425P#
I've had the Sony DVP-NS425P DVD player for a couple of years now and have had no problems with it until recently. The player will still read and play CDs just fine but now says 'Cannot play disc' for every DVD I pop in. I cannot seem to find any instruction manuals or help on this player online and the warrantee's already done so there's definitely no solution there. I can't seem to determine whether or not a setting's been changed and the menu doesn't seem to have an option for changing anything of that nature anyways. Can someone tell me if there's a setting (somewhere) that I can use to correct this problem without paying to have a specialist look at it?

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