Description of Safe Boot Mode in Windows 2000 (202485)


The information in this article applies to:

  • Microsoft Windows 2000 Server
  • Microsoft Windows 2000 Advanced Server
  • Microsoft Windows 2000 Professional
  • Microsoft Windows 2000 Datacenter Server
This article was previously published under Q202485
For a Microsoft Windows XP version of this article, see 315222.

SUMMARY

Windows supports several Safe Boot options that 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 when the Boot menu appears, press F8.
  2. When the Windows Advanced Options menu appears, select an option, and then press ENTER.
  3. When the Boot menu appears again, with the words "Safe Mode" displayed in red at the bottom, select the installation you want to start, and then press ENTER.
WARNING: Do not select a Microsoft Windows NT 4.0 installation.

Description of Safe Boot Options

  • Safe Mode (Safeboot_Option=Minimal): A minimal set of device drivers and services to start Windows.
  • Safe Mode with Networking (Safeboot_Option=Network): A minimal set of device drivers and services to start Windows plus the drivers necessary to load networking.
  • Safe Mode with Command Prompt (Safeboot_Option=Minimal): This is the same as Safe mode, with the exception that Cmd.exe is started rather than Windows Explorer.
  • Enable VGA Mode: This starts Windows in 640 X 480 mode using the current video driver (not Vga.sys). This mode is useful for cases in which the display was configured at a setting the monitor cannot display.

    NOTE: Safe mode and Safe mode with Networking load the Vga.sys driver instead.
  • Last Known Good Configuration: This starts Windows using a previous good configuration.
  • Directory Service Restore Mode: This mode is valid only for Windows domain controllers. It performs a directory service repair.
  • Debug Mode: This option enables debug mode in Windows. Debugging information can be sent across a serial cable to another computer running a debugger. This mode is configured to use COM2.
  • Enable Boot Logging: When the computer is started with any of the Safe Boot options except Last Known Good Configuration, logging is enabled. The Boot Logging text is recorded in the Ntbtlog.txt file in the %systemroot% folder.
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 Minimal.

The default Microsoft VGA driver is used for display (640 X 480 X 16 colors). You must log on in all modes (either by a domain or the local SAM, depending on which Safe Boot mode you choose).
Modification Type:MajorLast Reviewed:9/11/2003
Keywords:kbenv kbinfo KB202485
©2003 Microsoft Corporation. All rights reserved.