The optical drive has an exclamation point in the Device Manager

Scope of application:

Winndows XP Pro System, Windows 7 system

　　Knowledge Point Analysis:

1. The system in loading the optical drive equipment and other devices occupy the channel conflict; 2. After the virtual CD-ROM drive can not be used normally, from the Device Manager to see only the optical drive has an exclamation point, or have an incorrect optical drive;

　　Operation Steps:

Tip: There is a risk of modifying the registry, please back up your data in advance and operate under the guidance of a professional.

1. Click the lower left corner to start---run-> regedit.exe

Go to Registry Editor and find it in the item on the left.

HKEY_Local_Machine

SYSTEM

Currentcontrolsetcontrol

Class{4d36e965-e325-11c e-bfc1-08002be10318} is selected and the "UpperFilter" and "loweverfilter" items are found in the right window. Right-click to delete the "UpperFilter" and "Loweverfilter" items.

2. Uninstall the problematic optical drive in Device Manager, uninstall after the scan hardware changes, will find the optical drive. The CD drive is back to normal, and if the problem still does not work, restart the computer.

Sometimes there is no "UpperFilter" item, then only the "Loweverfilter" item can be deleted.