Hi
does the DVD writer show up in the BIOS (or UEFI) as a boot device?
If not probably dead drive or bad connection
Occasionally removing and re inserting DVD drive in laptop can cure the problem.
In very rare circumstances having IDE (ATA) hard disk controllers & SATA controllers enabled can prevent device manager seeing a DVD drive on SATA controller. (Happened to me at work recently)
regards
Mike Barnes