My DVD-CDROM works as CDROM only?!

[ngc7778]

Hi
i have a LG DRD-8160b DVD-CD ROM drive on my computer.
i didn't install any specific driver for this device.windows XP recognized it automatically. as DVD-CDROM.
it works perfectly as CDROM. but when i tried to use it as DVD(i put a DVD in tray)
i got a message " please insert a disk"
it doesn't work as a DVD ROM.
what causes the problem?
here is some additional information:
i have also a LG cd writer onboard!
my windows media player supports DVD video
DVDs are ok,they work with other devices.
any guidance and suggestion will be appreciated

small newbie

[big mac]

ello,
I had a similar problem - media player had codec problem. However, seen as W.xp did it automatically, mite not hav enabled DVD 'recognition'. u cud check this in BIOS, look for ur make, 'LG DRD-8160b', in 'peripheral settings' or 'advanced settings' (sorry, can't remember which). Should giv u list e.g. CD-ROM [enabled], VCD [enabled], DVD [disabled] etc. will definately b there seen as u can already play CDROMs. GUD LUK