Hi,
 
I have activated the UDMA66 mode using the registry : "HKEY_LOCAL_MACHINE\System\ CurrentControlSet\Control\Class\{4D36E96A-E325-11CE-BFC1-08002BE10318}\0000EnableUDMA66" = 1.
 
I don't know if that worked for the hard drives, but several hours after doing that (i didn't used the cd rom for 3 or 4 hours, so i didn't see the error), i noticed that no CD drives (one NEC DVD and one CD/RW drive) are available in the "My Computer". They now have an exclamation mark in the list of peripherals, saying that there is an error in the informations in the registry : damaged or incomplete (error 19).
 
In these several hours, i only installed Music Match Jukebox 6 but i don't think it is guilty...
 
I deleted the new added key, restarted : the same. I deinstalled the drives, resinstalled them : the same. I started with a boot log, it says it can't load the cdrom.sys driver... That's where the problem should be...
 
The strange thing is that Explorer can't list or access to this removable drives, but CDRWin or MusicMatch Jukebox 6 can read/write for them... It's also well recognized byt the BIOS.
 
What can i do ?
 
Thanks a lot, i don't know what to do and i don't want to reinstall everything...
 
Matzed.
 
Config :
Windows XP PRO
MSI 815EP Pro-R (6337)
PIII 800 EB 133
512 Mb RAM 133
1 HD Fujitsu 20 Gb 5400 tr/min
1 HD IBM 40 Gb 7200 tr/min and 1 HD WD 40 Gb 5200 Tr/min in RAID 0
1 DVD ROM DV5700A
1 CD/RW