I have never written a disk using xp software until today. When I put
a blank CD in it and did a properties it showed the disk was full. I
went to the properties and had to enable writing to the CD. I suspect
that it defaults to the disable position upon XP install. I put a
CDRW in it after I enabled writing to test it. It showed full again.
I brought up NTI and erased the CDRW and did a properties on it from
the desktop and it showed empty after that and wrote okay.

I can only suggest that you check to make sure the drives are enabled
to write under the recording tab, they may have all defaulted to off
when you did the xp install..

Hope this helps.