Anytime you get set to re-install Windows on your main hard drive,
you 1st backup certain files, like say your MSIE "Favorites" folder.
Does anyone have a list of files that they regularly backup every
time they re-install Windows?
While you could spend a lot of time compiling lists, the easier and safer
method is to make a FULL, incrementally restorable backup. For example, a
duplicate of the entire partition(s) either as a working, bootable backup
volume or a compressed image of the volume made with something like
DriveImage. DriveImage not only creates a partition image, but allows
for selectively restoring files.
You write "every time they re-install Windows" as if this is a regular
event. Why so many reinstalls? If you find you're regularly testing
software/etc that trashes a windows install you might want to have a 2nd,
testbed installation to preview (whatever) before putting the system's
primary OS installation at risk.