XP can't detect 2 out 5 external disks. Help!

Hello,

I use several external Maxtor disks, these are

2x My book WD 1 tr each.
1 Maxtor Onetouch IEEE 1394 SBP2 250 gig.
1 Maxtor Onetouch II USB & 1394 300gig
1 My Passport 320 Gig.
OS: XP SP3

I have never had any problems with running the disks. I could even run all of them at the same time with no problem. Recently I had to format my pc and after that. XP does not detect My passport and Maxtor Onetouch II.
When turning on the maxtor II, xp states "found USB Device" then I need to find the drivers to install.
Which of cours it does not find. Ends with " A problem accoured..etc. My passport reacts the same way.

Any solutions anyone.

Thank you.