Advanced Boot Options

Computer Studies BIOS

Even before Windows starts, there are many options during the boot process. The BIOS can be configured to boot from the floppy disk, the hard disk, a USB drive, CD:DVD drives or network adapters PXE (Preboot eXecution Environment)


Computer Studies Advanced Boot Options

Safe mode typically provides access to utility and diagnostic programs so a user can troubleshoot what is preventing the operating system from working normally. Safe mode is intended for maintaining the computer, not functionality, and provides minimal access to features. Microsoft Windows' safe mode is accessed by pressing the F8 key as the operating system boots.

If your computer will not start, you might be able to start it in safe mode. In safe mode, Windows uses default settings (VGA monitor, Microsoft mouse driver, no network connections, and the minimum device drivers required to start Windows).

If your computer will not start after you install new software, you might be able to start it with minimal services in safe mode and then change your computer settings or remove the newly installed software that is causing the problem. You can reinstall the service pack or the entire operating system, if necessary.

If a symptom does not reappear when you start in safe mode, you can eliminate the default settings and minimum device drivers as possible causes of the computer's inability to start.

The startup options are:

Safe Mode

Starts using only basic files and drivers (mouse,; except serial mice; monitor; keyboard; mass storage; base video; default system services; and no network connections). If your computer does not start successfully using safe mode, you might need to use the Recovery Console feature to repair your system.

Safe Mode with Networking

Starts using only basic files and drivers, and network connections.

Safe Mode with Command Prompt

Starts using only basic files and drivers. After logging on, the command prompt is displayed instead of the Windows graphical interface.

Enable Boot Logging

Starts while logging all the drivers and services that were loaded (or not loaded) by the system to a file. This file is called ntbtlog.txt and it is located in the %windir% directory. Safe Mode, Safe Mode with Networking, and Safe Mode with Command Prompt add to the boot log a list of all the drivers and services that are loaded. The boot log is useful in determining the exact cause of system startup problems.

Enable VGA Mode

Starts using the basic VGA driver. This mode is useful when you have installed a new driver for your video card that is causing Windows not to start properly. The basic video driver is always used when you start in Safe Mode (either Safe Mode, Safe Mode with Networking, or Safe Mode with Command Prompt).

Last Known Good Configuration

Starts using the registry information and drivers that Windows saved at the last shutdown. Any changes made since the last successful startup will be lost. Use Last Known Good Configuration only in cases of incorrect configuration. It does not solve problems caused by corrupted or missing drivers or files.

Directory Service Restore Mode

This is for the server operating system and is only used in restoring the SYSVOL directory and the Active Directory directory service on a domain controller.

Debugging Mode

Starts while sending debug information through a serial cable to another computer. If you are using, or have used, Remote Installation Services to install Windows on your computer, you might see additional options related to restoring or recovering your system using Remote Install Services.

Restoring your Computer

With Windows 2000 to restore your computer to an original setting you would use the Emergency Repair Disk. The facility in Windows XP Professional is the Automated System Recovery, ERD and ASR are referenced during the setup process which prompt you to repair your system, you should also perform a complete backup of your system and any important files anyway, but remember ERD and ASR do not backup your data.

To create an ASR disk go to start, all programs, accessories, and select backup from the menu, this opens the backup utility, here you can select the automated system recovery wizard.

To use the recovery disk you will need to insert the your original installation disk and press F2 to run automated system recovery, then you will need to insert your automated system recovery disk and re-install all the settings that were backup to that disk.

Windows Vista uses Windows Backup and Restore in Windows Vista you would go to start, all programs, maintenance, backup and restore center which opens up the backup and restore wizard to make backups of files or backing up the system or to restore your system to a previous backup.

To repair Windows Vista insert the installation disk, you are first prompted to select a language, time and currency format and the keyboard click next and instead of installing Vista on the next screen select repair your computer, select the operating system and the screen below opens offering the various choices.

To repair Windows XP insert the installation disk and at the welcome to setup screen select to repair a Windows XP installation using Recovery Console, press R. On the next screen select the operating system and press enter, you will be required to type in an administrator password to enter the setup to repair the computer.

Computer Studies Recovery

Boot Errors

Boot errors, usually the error messages are specific; try the recovery console to troubleshoot these problems. Typical error messages are.

Invalid partition table
Error loading operating system
Missing operating system
Operating system not found

You'll need the installation media and the administrator's password Make sure the boot option in the BIOS is set to the CD/DVD drive, insert the installation CD and after Windows installs the basic setup files; you will be prompted to install the operating system or to repair the operating system using the recovery console by pressing r.

After pressing r the next screen will give you a list of all the Windows installations to be found on the drive (if there's more than one operating system you will need to select the number of the operating system you're having trouble booting) after making your selection and typing in the number press enter, you'll next be prompted for the administrator's password type that in and press enter.

At the command line write fixboot and the drive of the boot sector such as C:\WINDOWS>fixboot c:

Then try re-booting the computer to see if the problem is solved.

If any of the boot files have been deleted from the drive by mistake. Typical error messages are.

A disk read error occurred
NTLDR is missing
NTLDR is compressed

You'll need the installation media and the administrator's password. Use the recovery console to access the CD drive with the installation media, you will need to change the directory to that of the CD drive by using C:\ >d: then type D:\>dir then change the directory by using the command D:\>cd i386\ntldr and copy the file using the command D:\i386>copy ntldr c:\ press enter this should copy the ntldr file to the C drive.

Useful web sites

Microsofts Home Page

Automated System Recovery

Windows Recovery Environment

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