Fix DVD Drive Not Recognized Problem After Installing Or Upgrading To Windows 7 Or Windows Server 2008 R2
Some users who installed Windows 7 or upgraded from Windows Vista/ XP to Windows 7 may face an issue with the DVD drive. It can go unrecognized. The problem in Windows Server 2008 R2.
According to Microsoft Knowledge base article KB976187, this problem occurs because the SATA driver (Msahci.sys) implements new power management functionality that is known as Adaptive Link Power Management (ALPM). Some optical drives do not behave correctly with ALPM enabled and may not be recognized by the computer.
The following is a list of some DVD drive models that are known to exhibit this problem:
TSST TS-L633B
PLDS DS-8A3S
A Hotfix is available from Microsoft Support site to fix this issue. You need to request and download from Microsoft Site. Below is the link for it. Microsoft Customer Support Service recommends that if your problem is not so severe, it better to wait for a while till Microsoft includes it in automatic updates or in Service Pack 1 for Windows 7.