Todays MS update made my Win7 unbootable

There was one critical update pushed from Microsoft today and when the
update finished and was ready for restart, my PC came up with a startup
error from which I could not get out even after booting up with the
Windows DVD in repair mode. Does anybody know what the number was for that
single KB file and did anybody else had this problem?
I tried several prior restore points but that did not work either.
Luckily I also have a Win10 laptop that I am using now, but I really liked
my Win7 PC better.
Unfortunately I don't have any recent system backup file from the
corrupted PC and I can only use individual data file transfers from the
Win7 PC after removing its HD and make it a temp. USB drive for my Win10
laptop.