Below are steps to help diagnose the issue with your computer recognizing your DVD drive:

1. Check to make sure the DVD Drive has an active connection with the system’s power cable and SATA cable.
2. Make sure the drive head is properly located.
3. If you’re using a separate drive controller, adjust the settings for the controller.
4. Check the type of optical drive you have installed, make sure its compatible with you system.
5. Check the system’s BIOS to make sure the optical drive is recognize.
6. Check the system’s Device Manager to verify the drive is installed. If there is an error, update the driver.