Since when this problem started?

Are you receiving any error message?

Run Windows Update and install all updates.

Hi,

Did you make any changes on the computer before the issue happen?

As Cyber_Defend_Team mentioned,did you get any error message?

To make it clear,please give us more detailed description about your problem.

I suggest that you check your DVD drive status in the Device manager first.

You can use the CD/DVD Fix it troubleshooter,which may automatically fix some problems.

Also,refer to the article to narrow down the issue:

http://support.microsoft.com/kb/314060

Hope this helps.

Regards,