Ok that is the problem then. Since you installed XP second, it obviously assigned C: to the boot partition, and I doubt now it would change it's drive letter.
I get my best advice from Technet. When I recently asked in several forums about changing a system drive letter with repair install, it got answered (No!) by a MS MVP expert on Technet.
They will help you sort this out.
You mean even if I wipe the 100m boot partition and repair win7 installation won't change the drive letters assigned?
My Computer
At a glance
Windows 7 Ultimate x64 rtm
- OS
- Windows 7 Ultimate x64 rtm