Windows Update Blew Away My Ethernet Driver

The recent Critical Windows Update blew away the original
native Intel Pro/100 Ethernet Driver on my IBM ThinkPad
P-III, leaving it dead in the water.

I eventually found a compatible Ethernet driver package at
Intel's site, but their download was too big to fit on a
floppy.

So I unpacked it to an antique '486 Win 95 machine in order
to make an emergency Ethernet driver install disk for the
crippled laptop.

I used that to reinstall the Intel Pro/100 Ethernet Driver,
but now the Ethernet runs no faster than 100 Kpbs, top
speed even on my local 10 Mpbs LAN. Trying to use this
machine over the public Internet is all but futile.
Downloads don't work at all, and even loading a simple
browser page takes forever.

I am chagrinned beyond words.