blu ray player won't recognise some disks

Once inserted, does My Computer show that the BR disc is there? Did the icon change?

Since older Blu-Ray movie discs play fine ... your problems sound exactly like the "DRM problems" people have playing very new discs on stand-alone Blu-Ray players.

I'm pretty sure that most people with stand-alone BD players have them connected to the net and keep the firmware updated, to enable playback of the latest titles ( I know I do).

http://en.wikipedia.org/wiki/Blu-ray_Disc#Digital_rights_management

In your case, I'm not sure if Lite-On or CyberLink is responsible for the DRM updates. If you find out, let us know.

You will probably need an update for PowerDVD from 8 to 10. Newer BD's do not play with version 8, I had to use 10 Ultra to play 2012 so you may need to do the same. The coding is different on newer BD's.

@ Chris M - Computer just shows the drive but no disc on the ones it does not accept

@ Tesla 1856- i'll check that out and let you know what happens

i have updated to PowereDVD 10 but still no joy.

also been through the PLDS site and there is nothing i can see or find that suggests i am missing some firmware (the smart pack utility from them tells me all is up to date)

So between the drive and software ... do you now have a daemon or background process that seems to run frequently (looking for updates)?

On the stand-alone players, the manufacturers (ie Sony, Panasonic, etc.) tend to stay fairly current ... but sometimes we have to wait a week or so (after a BD release date) before we can play the title (if it employs a radically new protection). Whoever is maintaining the database you use might lag behind even further.

 The only other thing I can think of is that we sometimes have to insert a SD Card into our dedicated players so it has some "work space" for certain titles. But with all the different forms of temporary storage available on a PC (by default) you wouldn't think that would be required.

So, you have PowerDVD playing all DVDs and most Blu-Rays (from the original optical discs) right?

yep i have all dvds and some blurays playing from PowereDVD 10 now.

but i had a slightly bigger problem through my own stupidity. i wondered if there was something in windows update that might help so had a peek and installed one that was to to with ATI (my card is a Radeon HD 5870). i knew i shoudn't, and i can hear some of you cringing just now, but i hit install for some mad reason and bang.

the card had errors, monitor would not show correct resolution etc. i got that sorted eventually but Catalyst Control Center would not open and the monitor image was underscanned so i could not get in to overscan it. eventually got that working again but took hours. and all because i could not play a couple of blurays that still won't play. i'm feeling pretty stupid right now. the Aurora is far to good a machine to have someone like me messing with it

I don't know if you know this but some of the Dell drives can be flashed to their retail versions. For instance the Dell BH20N Blu-Ray player/burner is really a LG BH08LS20 but without the lightscribe. The LS in the number stands for Lightscribe and the N in the OEM one means non-lightscribe. Other then that they are the exact same drivers. By flashing it to the retail versions you get the better speeds and newer formats.

 Find out what retail version yours really is and then go from there. Google it and you should have no trouble finding the sites where people do this and the firmwares for it. This may allow it to run the newer Blu-Rays it can't run ATM.

Keep in mind there is a chance you can harm the drive. If you do reflash it and something does goes wrong remember you did it at your own risk.