Here are answers to some common questions about Last Known Good Configuration.

Show all

What is Last Known Good Configuration?

It's a Windows startup option that uses the most recent system settings that worked correctly. Every time you turn your computer off and Windows shuts down successfully, important system settings are saved in the registry. You can use those settings to start your computer if a problem occurs. For example, if a new driver for your video card is causing problems, or an incorrect registry setting is preventing Windows from starting correctly, you can restart your computer using Last Known Good Configuration.

When should I use Last Known Good Configuration?

Try using Last Known Good Configuration if you can't start Windows, but it started correctly the last time you turned on the computer.

If you notice your system behaving strangely and Windows is still running, try using System Restore to return the system to an earlier point in time when things worked correctly. Unlike Last Known Good Configuration, changes made with System Restore can be undone (unless made in safe mode), and System Restore provides different points in time you can restore your system to. For more information, search Windows Help and Support for "System Restore."

Will Last Known Good Configuration affect my personal files?

No, it only affects system settings and won't change your e‑mail, photos, or other personal data on your computer. It won't help you recover a deleted file or a corrupted driver. To do that, you need to have previously backed up the data, or you need to reinstall the driver from the original source.

How do I start the computer using Last Known Good Configuration?

Follow these steps:

  1. Remove all floppy disks, CDs, and DVDs from your computer, and then restart your computer.

    Click the Start button Picture of Start button, click the arrow next to the Lock button Picture of Lock button, and then click Restart.
  2. Do one of the following:

    • If your computer has a single operating system installed, press and hold the F8 key as your computer restarts. You need to press F8 before the Windows logo appears. If the Windows logo appears, you will need to try again by waiting until the Windows logon prompt appears, and then shutting down and restarting your computer.

    • If your computer has more than one operating system, use the arrow keys to highlight the operating system you want to start, and then press F8.

  3. On the Advanced Boot Options screen, use the arrow keys to highlight Last Known Good Configuration, and then press ENTER.

  4. If your computer has more than one operating system installed, use the arrow keys to highlight the operating system that you want to start by using Last Known Good Configuration, and then press ENTER. Windows will then resume starting normally.