Last week I was trying to help a remote client whose Windows XP machine was really messed up. More than half of her automatically starting services refused to start at bootup. They couldn’t be manually started either, system restore was turned off, and she was in a hotel far, far away from any Windows XP CDs that she could have used in a repair.
Her Internet Explorer refused to launch, even after reseting it using RIES. Luckily she had Firefox installed, so she was able to download my UltraVNC SC executable so I could remotely control her machine.
Nothing I tried fixed her machine, so my last hope was to boot using the Last Known Good Configuration. I tried to explain to her how and when to press F8 to get into XP’s boot menu, but she just couldn’t do it. She must have tried 10 times, but missed it every time.
I decided there had to be a way to invoke Last Known Good Configuration other than pressing F8; maybe a registry entry, a script, or something. I searched and searched, but couldn’t find an alternative way of booting with Last Known Good Configuration.
I finally came across this Boot.ini reference on the Sysinternals portion of the Microsoft web site. If you edit your boot.ini to include the /lastknowngood switch, you’ll boot into the Last Known Good Configuration.
I edited the boot.ini to include /lastknowngood, and it did indeed boot into the Last Known Good Configuration. Unfortunately, that version was as messed up as her regular booting version was. Once she got back from her conference we did an XP repair on the system, and it started functioning normally again.
KB 307852 explains that when you start your computer by using the Last Known Good Configuration feature, Windows XP restores information in the following registry key:
and any changes that were made to other registry keys remain