Using system restore, the OS is set back to a time before the problem started. This often cures such problems.
When the update (just before the update) is installed, a restore point is created.
If that (day) restore point fails to function, try an earlier one. Keep trying different dates until you find one that is suitable.
This does not erase your personal files...only turns back the clock on the OS.
System update can cause problems due to incompatibility with some computers, hardware, drivers, etccc....
not every system has problems, only some. I have had several issues with several systems.
I turn off the automatic updates entirely, and so do many other people.
A. I can load "critical updates only." I can choose which updates to install, one at a time.
B. I can check the manufacturer website to find a possible list of incompatible updates.
C. I rely on a professional antivirus, not microsoft updates, to keep my computer safe. (I don't recommend free antivirus...)
D. Don't be obsessed with updates. It's not the end of the world if you fail to install them.
If windows will start normally: (with windows running)
turn off all security, antivirus and firewall.
Put the windows 7 install disk in the drive and run, select "upgrade."
This reloads the operating system, does not erase your files or programs.
This will eliminate all updates. Now you can start with a clean, non- updated system.
If you turned the auto update "off," you can choose updates, manually. Critical updates only perhaps.
After installing updates you choose, turn the antivirus and firewall back on.
On the otherhand, if you turn automatic updates "on,"
eventually, the same update will automatically install, and cause the same problem again...
knocking you back to square one....