Firewire was unloved by Microsoft for years. Even today I don't reccomend firewire for hard disks on the Windows OS. But do for the Apple OS.
This is borne by having to help too many recover files from firewire drives on Windows. I don't want to debate this, but only to share my experiences.
You will find some that can't resist and will trumpet items why it should be better but the risk is too much in my book. Move back to USB 2.0 and see if it just works.
If you feel it should work, pester your PC maker and Microsoft.
I've ignored this inconvenience for a while but thought I'd try to find a solution here. I have a Dell Dimension, XPPro with a firewire desktop recorder and 2 FW daisy chained HDDs in Adaptec enclosures.
XP will only recognize 2 devices at a time. If I shutoff the recorder before boot, the other 2 drives will be enabled and work fine. I'd like to use all 3 simultaneously but don't know what's causing the problem. Any ideas or suggestions would be appreciated.