I've just fixed a similar problem with my read-only DVD-Drive --- not sure how but never mind here is what I did ...
DVD-Drive was suddenly not recognising CDFS discs such as software, music, audio, vcd, pc games etc. UDF dics, ie DVD, still working fine ...
What I did was create a system restore point, insert the recovery cd that came with the laptop and the DVD-Drive immediately recognised it as a CDFS disc.
I reloaded Power DVD and after that the DVD-Drive recognised all CDFS discs that I inserted !!!
Why ? who knows ...
It blipped about 5 minutes later and stopped recognising them again including the recovery disc. All I did was restore back to the restore point I'd created, inserted the recovery disc again, reloaded Power DVD again and voila it's all working again ---
Weird ? sure is !!!
Checked everything again this morning including DVD UDF discs and all is still working back to normal.
What went wrong ? who knows ...
What fixed it ? who knows ...
Will it happen again ? probably - just hope the same "fix" fixes it the next time it all goes wrong !
The wonders of rocket science eh ...
CDFS in System Information is still showing disabled and running so the lead to be enabling that must have been up-the-garden path or is only applicable to Read/Write drives or something else - sorry about that ...
Thx everyone for your input. If you're having the same problem I do hope you get to fix it as easy as this "fix" "fixed" mine this time round !
George
On the CDFS and UDFS front --- was advised following:
CDFS: re-enabling the service:
Boot from the Windows XP CD
Select R to repair
Select C for Recovery Console
Select the windows installation
Type the Administrator password
Type in "listsvc" to make sure cdfs is not set to SERVICE_AUTO_START
Type in "enable cdfs service_auto_start"
Type Exit to reboot
I'd chek out the same for the UDFS
