You Cannot Use the "Start Windows Using Last Known Good Configuration" Feature to Remove SP1

After you install Windows XP Service Pack 1 (SP1), you cannot use the "Start Windows Using Last Known Good Configuration" feature to undo the installation of Windows XP SP1. To undo an installation of SP1, use the Add or Remove Programs tool in Control Panel.

SP1 removes files from the Windows\LastGood folder during the setup and removal processes to prevent problems that may occur if you use the "Start Windows Using Last Known Good Configuration" feature to undo an installation of SP1.

To use the Add or Remove Programs tool in Control Panel to undo an installation of SP1 follow these steps:

1. Start the Add or Remove Programs tool in Control Panel.
2. In the list of currently installed programs, click Windows XP Service Pack 1, and then click Remove.

NOTE: If you choose not to archive files when you install Windows XP SP1, Windows XP SP1 is not listed in Add or Remove Programs and therefore you cannot remove it. Also, if you install updates to Microsoft Internet Explorer after you install Windows XP SP1, Windows XP SP1 may not be listed in Add or Remove Programs. In this case, you can remove the updated version of Internet Explorer to restore Windows XP SP1 to Add or Remove Programs.