Asus E616 DVD Rom problem

I can no longer use my Asus E616 for playing DVDs although it will play
audio CDs though it takes its time before it is ready to play the CD.

My DVD program CyberLink PowerDVD 6 correctly identifies the DVD player as
'drive G' but any DVD disk is not recognised and the program responds with
'no disk'.

The device is shown to be working correctly and I have tried uninstalling it
and rebooting the system whereupon it is detected.

The problem appears to be that the DVD Rom is being associated each time I
remove it with the following inf. file when rebooting the system:-

C:\winnt\inf\cdrom.inf

As far as I am aware it should be associated with:-

C:\winnt\inf\dvdrom.inf

I am at a loss as to how I can get it to recognise the dvdrom.inf file, if I
copied it to a disk and then under install new driver chose the option "have
disk" would this work?

I am a novice at all this!

Agzee