Wrong Keyboard Layout – HP Laptop

Having just installed a fresh copy of XP pro on my HP Pavilion Laptop, installed all the drivers, set everything I can find to UK, I find I still can’t use Back-Slash key which is directly to the left of the “Z” key on my keyboard, which makes it a 102 type I beleive.
I can’t find anyway of telling XP, I thought it might be a special driver, but HP say it’s a Windows problem and suggest I contact Microsoft. Microsoft say it’s a HP problem as the keyboard is unique to HP ! So where do I go fromthere ?
I’m sure it must be an easy fix if only I could find it.
Regards, Dave Baker