I have lg dvd writer. model no GCC-H21N .dvd not reading

This is due to a weak lens
Sometimes this type of problem occours due to excessive use of the drive in burning cd/dvd

Trying some leans cleaner may solve your problem

> CD-RW / DVD-ROM

Sorry, but this device is not a DVD-writer.

This device _should_ read (non-blank) DVD media.
If it does not, then the cheapest solution is to spend $40
to buy a new CD/DVD reader/writer.

Combo drives have 2 lasers inside of them. An IR laser to read CD/VCD and a red laser to read DVD. It sounds like your laser to read DVD discs is dirty or has developed a fault. A replacement drive would be your best option as they are now very cheap and it will resolve the issue quickly.
Hope this helps,
www.PuterCare.com

Please the following document for WS XP user

http://h10025.www1.hp.com/ewfrf/wc/document?docname=bph07146&cc=us&dlc=en&lc=en&jumpid=reg_R1002_USEN

and for WS Vista

http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00817052&cc=us&dlc=en&lc=en&jumpid=reg_R1002_USEN

If you own a cleaning disk for CD players, use it, if not, buy one (not expensive) and if that fails, replace the drive. They are not expensive as new but could be very costly to repair.

may be it is only CD rom...

My DVD writer didn't read the dvd's.

If not reading DVD is a pattern (it won;t read ANY DVD, no matter if it's a burned one or an original movie) then the lens is dead. I'm afraid you'll have to go get a new one (new drives are very cheap, usually around 25-30$)

help me ok