Hi,
Please follow the steps mentioned below and check if they help.
Step 1:
I would suggest you to check if you’re able to see the files from the command prompt.
a. Click Start, and then type cmd in the Start Search box.
b. Right-click cmd in the Programs list, and then click Run as administrator.
If you are prompted for an administrator password or confirmation, type your
password or click Continue.
c. In front of the CD/DVD drive letter, type DIR and check if you’re able to find the files.
Step 2:
Also, try to open the DVD from Windows media center.
Try to run the Fix it from the link below that talk about Your CD drive or DVD drive is missing or is not recognized by Windows or other programs
http://support.microsoft.com/kb/314060
If none of the above steps are of any help, I would suggest you to open the DVD in another computer, copy the files to the drive and burn the DVD again.
Azeez Nadeem - Microsoft Support
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