Microsoft KB Archive/315222

= A description of the Safe Mode Boot options in Windows XP =

Article ID: 315222

Article Last Modified on 1/31/2007

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APPLIES TO


 * Microsoft Windows XP Home Edition
 * Microsoft Windows XP Professional
 * Microsoft Windows XP Professional for Itanium-based systems

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This article was previously published under Q315222





For a Microsoft Windows 2000 version of this article, see 202485.



INTRODUCTION
This article discusses the several Safe Boot options that Windows supports. These options load a minimal set of drivers. You can use these options to start Windows so that you can modify the registry or load or remove drivers.



MORE INFORMATION
To use a Safe Boot option, follow these steps:
 * 1) Restart your computer and start pressing the F8 key on your keyboard. On a computer that is configured for booting to multiple operating systems, you can press the F8 key when the Boot Menu appears.
 * 2) Select an option when the Windows Advanced Options menu appears, and then press ENTER.
 * 3) When the Boot menu appears again, and the words &quot;Safe Mode&quot; appear in blue at the bottom, select the installation that you want to start, and then press ENTER.

Description of Safe Boot options

 * Safe Mode (SAFEBOOT_OPTION=Minimal): This option uses a minimal set of device drivers and services to start Windows.
 * Safe Mode with Networking (SAFEBOOT_OPTION=Network): This option uses a minimal set of device drivers and services to start Windows together with the drivers that you must have to load networking.
 * Safe Mode with Command Prompt (SAFEBOOT_OPTION=Minimal(AlternateShell)): This option is the same as Safe mode, except that Cmd.exe starts instead of Windows Explorer.
 * Enable VGA Mode: This option starts Windows in 640 x 480 mode by using the current video driver (not Vga.sys). This mode is useful if the display is configured for a setting that the monitor cannot display.

Note Safe mode and Safe mode with Networking load the Vga.sys driver instead.
 * Last Known Good Configuration: This option starts Windows by using the previous good configuration.
 * Directory Service Restore Mode: This mode is valid only for Windows-based domain controllers. This mode performs a directory service repair.
 * Debugging Mode: This option turns on debug mode in Windows. Debugging information can be sent across a serial cable to another computer that is running a debugger. This mode is configured to use COM2.
 * Enable Boot Logging: This option turns on logging when the computer is started with any of the Safe Boot options except Last Known Good Configuration. The Boot Logging text is recorded in the Ntbtlog.txt file in the %SystemRoot% folder.
 * Starts Windows Normally: This option starts Windows in its normal mode.
 * Reboot: This option restarts the computer.
 * Return to OS Choices Menu: On a computer that is configured to starting to more than one operating system, this option returns to the Boot menu.

An environment variable is set when you use one of the Safe Boot options. The environment variable is SAFEBOOT_OPTION. This variable is set to either Network or to Minimal.

The default Microsoft VGA driver is used for display at 640 x 480 resolution and in 16 colors. You must log on in all modes by a domain or by the local Security Accounts Manager, depending on which Safe Boot mode you select.

Keywords: kbenv kbinfo KB315222

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