Recipe 3.5. Using the Last Known Good Configuration to Resolve Hardware Problems

Problem

A device you recently installed, or that has failed, can force Windows into the boot menu or prevent Windows from booting up.

Solution

1. During Windows startup press the F8 key to access the Start menu.

2. Using the cursor keys, select Last Known Good Configuration.

3. Press the Enter key to restart.

Discussion

Windows saves Registry data about the last time the system started and ran properly, which is known as the Last Known Good Configuration. When you make this selection from the Start menu, Windows replaces settings known to work from a prior complete startup into the Registry and restarts using them. Using this method has one small flaw in that an automatically configured Windows installation with the SYSPREP utility and then setup scripts may use generic drivers and settings, setting the system to use new drivers at next restart and leaving the system with a prior good configuration to go back to. SYSPREP is a Microsoft tool that removes all traces of prior users, custom settings, mapped drives, network connections, PC hostname everything that reveals how a system administrator or another user has configured the system. SYSPREP allows administrators to configure new PCs and then give their users a fresh, clean XP experience the first time they boot up, without someone else's clutter in the way.

Since you may not be able to restart and access Window's System Restore feature, the Last Known Good Configuration feature is a subset of a full System Restore Point, which will roll back all Windows changes since a given time. This feature reverts your system to working hardware configurations without affecting software or system configuration changes. If using the Last Known Good Configuration option does not work, you need to boot to Safe Mode to run System Restore, or finally, sadly, reinstall Windows, and provide known good drivers.

See Also

Snippets of details about the Last Known Good Configuration can be found throughout the Web. Most compelling are tips to disable the feature should you find yourself stuck and not wanting to use the last boot configuration. Check out http://www.compphix.com/somefactaboutlastknowngoodconfig.html, http://www.windowsitpro.com/Article/ArticleID/14852/14852.html, and http://www.winguides.com/registry/display.php/851/.