16.9 Safe Mode and the Startup Menu


PC troubleshooting is among the most difficult propositions on earth, in part because your machine has so many cooks. Microsoft made the operating system, another company made the computer, and dozens of others contributed the programs you use every day. The number of conflicts that can arise and the number of problems you may encounter are nearly infinite. That's why, if you were smart, you bought your PC from a company that offers a toll-free, 24- hour help line for life. You may need it.

If the problems you're having are caused by drivers that load just as the computer is starting up, turning them all off can be helpful, at least so that you can get into your machine to begin your troubleshooting pursuit. That's precisely the purpose of the Startup menu ”a menu most people never even know exists until they're initiated into its secret world by a technically savvy guru.

Making the Startup menu appear is a matter of delicate timing. It goes like this:

  1. Restart the computer. Immediately after the BIOS startup messages disappear, press the F8 key (on the top row of most keyboards).

    The BIOS startup messages ”the usual crude-looking text on a black screen, filled with copyright notices and technical specs ”are the first things you see after turning on the computer.

    If you press the F8 key after the Windows logo makes its appearance, you're too late. If you've done it right, on the other hand, you see a message that says, "Please select the operating system to start." Most people have only one option here ”"Microsoft Windows XP Professional."

  2. At the "Please select the operating system" screen, press F8 again.

    If all goes well, you'll see the Windows Advanced Options Menu (see Figure 16-16). Displayed against a black DOS screen, in rough lettering, is a list of options that includes Normal, Logged, Safe Mode, and so on.

    Figure 16-16. The Startup menu (not to be confused with the Start menu) appears only when you press F8 a couple times as the computer is starting up. In times of deep trouble, it can be a lifesaver.
    figs/16fig16.gif
  3. Select the startup option you want.

    To make a selection, press the up or down arrow keys to "walk through" the list. Press Enter when you've highlighted the option you want.

Here's what the Startup menu commands do:

  • Safe Mode . Safe Mode starts up Windows in a special, stripped-down, generic, somewhat frightening-looking startup mode ”with the software for dozens of hardware and software features turned off. Only the very basic components work: your mouse, keyboard, screen, and disk drives . Everything else is shut down and cut off. In short, Safe Mode is the tactic to take if your PC won't start up normally, thanks to some recalcitrant driver.

    Once you've selected the Safe Mode option on the Startup menu, Windows asks which operating system you want to run ”for most people, Windows XP Professional is the only choice, so just press Enter. Now you see a list, filling your screen, of every driver that Windows is loading. Eventually, you'll be asked to log in; a dialog box then appears, reminding you that you are in Safe Mode.

    This dialog box offers two useful buttons . Yes proceeds with the startup process, taking you to the Windows desktop. Clicking No takes you directly to the System Restore screen shown in Figure 16-2, so that you can choose a date when your computer was running properly ”and rewind to that happier time.

    You'll probably discover that your screen looks like it was designed by drunken cave men, with jagged and awful graphics and text. That's because in Safe Mode, Windows doesn't load the driver for your video card. (It avoids that driver, on the assumption that it may be causing the very problem you're trying to troubleshoot.) Instead, Windows XP loads a crude, generic driver that works with any video card.

    NOTE

    Note, by the way, how fast Windows is in this mode ”a testimony to the dragging effect of all those modern graphic niceties.

    The purpose of Safe Mode is to help you troubleshoot. If you discover that the problem you've been having is now gone, you've at least established that the culprit is one of the drivers that Windows has now turned off. Safe Mode also gives you full access to the technical tools of Windows XP, including System Restore (Section 16.1), the Device Manager (Section 14.6), the Registry Editor (Section 16.10), Microsoft Backup (Section 16.7), and the Help center. You might use the Device Manager, for example, to roll back a driver that you just updated (Section 14.7), or System Restore to undo some other installation that seems to have thrown your PC into chaos.

    If this procedure doesn't solve the problem, contact a support technician.

  • Safe Mode with Networking . This option is exactly the same as Safe Mode, except that it also lets you load the driver software needed to tap into the network, if you're on one ”an arrangement that offers a few additional troubleshooting possibilities, like being able to access files and drivers on another PC. (If you have a laptop that uses a PC-Card networking card, however, this option still may not help you, since the PC-Card driver itself is still turned off.)

  • Safe Mode with Command Prompt . Here's another variation of safe mode, this one intended for ultra -power users who are more comfortable typing out text commands at the command prompt (Section 7.1.7) than using icons, menus , and the mouse.

  • Enable Boot Logging . This startup method is the same as Normal, except that Windows records every technical event that takes place during the startup in a log file named ntbtlog.txt (it's on the startup drive, in the Windows folder).

    Most of the time, you'll use the Boot Logging option only at the request of a support technician you've phoned for help. After confirming the operating system startup, the technician may ask you to open ntbtlog.txt in your Notepad program and search for particular words or phrases ”usually the word "fail."

  • Enable VGA Mode . In this mode, your PC uses a standard VGA video driver that works with all graphics cards, instead of the hideously ugly generic one usually seen in Safe Mode. Use this option when you're troubleshooting video-display problems ”problems that you are confident have less to do with drivers than with your settings in the Display control panel (which you're now ready to fiddle with).

  • Last Known Good Configuration . Here's yet another method of resetting the clock to a time when your PC was working correctly, in effect undoing whatever configuration change you made that triggered your PC's current problems. It reinstates whichever set of drivers, and whichever Registry configuration, was in force the last time the PC was working right. (This option isn't as effective as the newer System Restore option, however, which also restores operating-system files in the process.)

  • Directory Services Restore Mode . This extremely technical option is useful only in corporations with specialized domain controller computers running Windows .NET Server or Windows 2000 Server.

    POWER USERS' CLINIC
    The Recovery Console

    Between System Restore and Safe Mode, everyday Windows users are well equipped to recover from most typical Windows snafus. But there are times ”extremely rare ones, thank goodness ”when the files of Windows itself are so corrupted that you can't even access these tools.

    In those situations, technically proficient PC fans can take advantage of something called the Recovery Console. As in DOS or UNIX, this window displays nothing but text ”no icons, menus, or other graphic niceties ”but if you know the correct commands to type, Recovery Console can help get you out of some very tight scrapes. It lets you manipulate files and folders, turn off specific drivers or background services, perform certain hard drive repairs , and even erase ( reformat ) drives.

    To prevent unscrupulous techies from exploiting this emergency tool, Recovery Console offers access only to the system files and folders of Windows itself ”application and document folders are off-limits ”and doesn't let you copy files onto floppies, Zip disks, or other removable disks. Otherwise, however, Recovery Console looks and works much like the standard DOS command prompt. (Type help ”and then press Enter ”to see a list of all the commands you can use.)

    To access Recovery Console, restart the PC from your Windows XP Professional CD-ROM. (On some computers, of course, you can't start up from a CD until you first adjust settings in the BIOS. Ask your PC's manufacturer for help.)

    When you see the Welcome to Setup screen, press the R key, and then type and the number corresponding to the copy of Windows you want repaired. When you're asked for the password, just press Enter.

    When you're finished making your repairs, type exit to get out of Recovery Console and restart the PC.


  • Debugging Mode . Here's another extremely obscure option, this one intended for very technical people who've connected one PC to another via a serial cable. They can then use the second computer to analyze the first, using specialized debugger software.

  • Start Windows Normally . This option starts the operating system in its usual fashion, exactly as though you never summoned the Startup menu to begin with. The Normal option lets you tell the PC, "Sorry to have interrupted you go ahead."

  • Reboot . Choose this command to restart the computer.

  • Return to OS Choices Menu . Use this choice to back up to the "Please select the operating system to start" screen that first appeared when you pressed F8 during startup.



Windows XP Pro. The Missing Manual
Windows XP Pro: The Missing Manual
ISBN: 0596008988
EAN: 2147483647
Year: 2003
Pages: 230

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