windows easy transfer fills boot drive

I am trying to run windows easy transfer and there must be some basic thing
I am missing. I am running Vista Ultimate SP 2 on the old machine and I am
moving to windows 7 Ultimate. Both are 32-bit versions. I specify a
network drive as a target. I am trying to transfer settings and not most
files, because I have a good backup. The tool calculates that it will need
8 GB of space and there are 500GB free on the target drive. Easy transfer
fails. When he is done, there is a 24-byte file on the network drive, and
it has completely filled the boot drive on the machine the tool is running
on. I was able to find a 46GB file on the C: drive where it has put the
stuff.