Hi bbond007, thanks for your help. 
why 1fe00 rather than 0x1fe00?
Is it ok to use lower case aswell?
You are right, it should be 0x1fe00, I just delete up to the 0x, so I forgot about that part.
Lower case is fine, but you do need the 0x and to press [ENTER]
My fast ATA controller splits my 60GB drive into 15 4M drives, so I must have set that mask a million times now
