Can't upgrade from XP to Vista on dual boot Dell.

[Pinio]

I have dual boot machine Windows XP and OSX 10.4.8.

I can't upgrade Windows partition from XP to Vista.

When I tried to do it from Windows, system tells me that there is not enough space on partition for files, despite the fact that I have around 100 GB free on this partition.

So, I started from Vista bootable disk, also with the error that Vista can't be instlled on this partition.

I even deleted Windows partition and create new one and start from scratch, but the same thing. Vista does not like this new partition.

Is it any way to fix this problem?

Is it something to do with MBR and OSX Darwin boot I am using?

Thanks for your help in advance,

Pinio