This is my 10th time figuring out the solution for a problem with an old ABIT mobo (TH7-Raid) I can ever find the solution posted, so I write it expecting may be usefull for anyone else (and for next time I reinstall XP )...

Problem:
During Windows XP Installation, you didn't use the F6 option to install a external SCSI/RAID driver, so Windows tried to install its database driver but it it doesn't have one and then failed. However it left the driver entry in the scsi.inf file in windows/inf so every time you try to install another one it automatically uses this entry and fails again with the message:

"The driver installation file for this device is missing a necessary entry. This may be because the INF was written for Windows 95 or later. Contact your hardare vendor."

Don't panic, not necessary to reinstall Windows, you just need to manually install the driver with no devices connected to the HPT370.

Solution:
Disconnect power to all HPT370 devices.
From Control Panel,
Add Hardware,
Next,
<Searching>,
"Yes, I have...",
"Add a new hardware device",
"Install Manually",
"SCSI and RAID controllers",
"Have a Disk",
find your HPT370 v2.351 driver,
next, next, next...
From Device Manager,
Select the double SCSI / RAID device not working and uninstall it.
Rescan devices and voila!!!! The bad one is gone and everything is in place...
Shut down, reconnect your HPT370 devices, reboot.

Hopefully may be usefull for someone...