Crash After definition update for windows defender - kb915597

While in Internet Explorer, my Windows 7 SP1 64-bit system froze.
I had to hard reboot it and tried to get into System Restore. I could not type into the command line or open Control Panel. This went on for 2 hours.

Somehow I got into System Restore and restored to before a Windows Update for:

definition update for windows defender - kb915597 (Definition 1.191.3347.0)

Seems OK now, but would like to know what happened.

Any ideas?
cb

Try the update again. Sometimes it just fouls out, but rarely.

Make sure you have System Restore turned on and plenty of disk space apportioned to it: System Protection - Change Disk Space Usage

If necessary you can always access System Restore from System Recovery Options by the various methods shown. I'd make my System Repair Disk if you don't have the Win7 installation media to boot.

I was afraid to try to boot into safe mode and use System Restore. My "Missing Manual" book says if I do that or in Windows Recovery Mode, it cannot be undone.

System Restore said it was a Critical update, but when I looked at Update History, it said it was an Important update??

I have it set to do Critical updates automatically. The others, I do manually.

I do have the original installation disks from before SP1. Should I make System Repair Disk now?

cb

Yes, or the latest installation media from Troubleshooting Windows 7 Failure to Start

My desktop system crashed again after a critical update of kb915597. (My post of 01/29/2015.)

I got all kinds of bad messages when I tried to reboot, System Restore, Startup Repair, Cannot repair this computer automatically...

After several hours of trying to do it, I was finally able to restore to before the critical update.

I am trying to nurse this desktop Windows 7 system along until Windows 10 is available. I do not want to learn Windows 8. Is there a way I can tell it to download critical updates, but not install them so I can avoid this update?

Thanks, cb