a web search came up with a number of ideas, this one requires a registry edit.
http://answers.microsoft.com/en-us/windows/forum/windows_xp-hardware/dvdcd-rom-drive-reads-cds-but-does-not-read-dvds/a2e8ed49-0c67-4ab9-b5fe-33d767bca3a4
.
I can't say that this will work or not, but a web search on 'drive reads cd but not dvd' comes up with a bunch of links with other ideas.
Paul Hachmeyer  

-----Original Message-----
From: Personal Computer Hardware discussion List [mailto:[log in to unmask]] On Behalf Of Russ Cox
Sent: Monday, March 03, 2014 10:51 AM
To: [log in to unmask]
Subject: [PCBUILD] Computer won't read DVDs

I have an older Compaq D510s computer, 2.5 GHz Pentium 4, 2.5 GB ram. I have loaded Win XP, then Win 7. I have tried two different DVD drives, but the computer won't read the DVDs. The drive is recognized and there is no update for the drivers. The drive will read a CD, but not a DVD.
A second D510s running Win 7 does read DVDs.
Any ideas?

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