sfc /scannow problem

Archived from groups: microsoft.public.windowsxp.perform_maintain (More info?)

I recently encountered a problem with various functions on my PC
malfunctioning, MSN Explorer, Fonts etc. and decided to do the sfc /scannow
to correct XP. It asked for my disk, which I inserted. I was given the
option (eventually) to do an "Upgrade" install. All went well, until it
reached the "Installing Network" stage. It stuck there and refused to move
along. My only alternative at that stage was to reboot, reformat my HDD and
reinstall Windows.
Three questions....
1. I tried to "Repair" MSN Explorer using the Add/Remove Windows Components
module but all it did was try to reinstall it (there was no repair option),
and it failed to correct the problem. Why wouldn't that work?
2. Why would the "Upgrade" installation stall at the stage it did?
3. Should I have not selected the "Upgrade" option and gone for full
installation but then done a repair (which I believe would have been an
option at a later stage)?
I've since moved the i386 folder to my C:\ drive and altered the set up in
HKLM to sourcepath C:\ but haven't tested it.

--
Peter.
Toronto, Canada.
Windows XP Home SP2.
P4 dual HT @ 3.0ghz, 160gb HD, 1.0gb DDR.