Port the patch[1] for whatever eucalyptus version you use. I did it for 1.6.1 and works like charm. I will push the patch for 1.6.1/1.6.2 and 2.0 in couple of days. Follow the steps as it is, it will work fine. Currently I am using XP and 2003 server on eucalyptus 1.6.1
[1] http://forum.eucalyptus.com/forum/patch-windows-support-eucalyptus-xen
Are you saying that windows instance worked with 1.6.1 ? Is it after modifying the file - gen_kvm_libvirt_xml ?
I could get it to work after changing the ramdisk to 0 & remove the line which talks about kernel ?
Can you shed some light into this please ?
Cheers
Sundar