Lately I´m experiencing a problem with playing new dvd movies on my laptop. The fact is that neither the internal dvd player nor the external burner LG GSA-5120D, see the inserted media. If I insert lets say a two year old original movie or burned copy of any movie, both see the media and play it ok. This only happens with new movies.
I need a helping hand cause I´m not much good with computers and cann´t figure out what the problem may be.
Thanks in advance. 
Insert the disk, startup a software dvd player and select the drive…
What happens?
Thanks Chef for yr. reply to my query. I´ve tried with media player classic and videolan player and got no results, still the cd/dvd unit not seeing the inserted media. Afterwards I re-installed the WinDVD player which comes with original compaq soft. and voila! everything comes alive, both units can play.
Thanks so much for yr help
Yep, windvd probably removed the codecs/files you need to play the dvd when you unistalled the program.