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Windows 98 Professional Reference

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- 36 -
The Windows 98 Boot Process and Emergency Recovery

Sometimes you find yourself in a jam--a real jam, where your system won't start. What's the problem? What to do? How to handle it? That's part of the subject of this chapter: Emergency Recovery. Chapter 37, "Tools and Strategies for Troubleshooting Windows 98" covers dealing with individual hardware devices, software that isn't working correctly, or other aberrant behavior on your system. But Chapter 37 assumes that your system is starting (more or less). Not here, though: This chapter will get you on the road to recovery when you can't even get the darn thing booted. And because emergency recovery is closely related to how Windows 98 boots, you'll also learn about the Windows 98 boot process in this chapter.

In this chapter you learn about the following:

Startup problems can be among the most frustrating because you have so little information with which to work. There are no friendly little trouble icons in Device Manager to show you where the trouble is, usually. As you will see, however, solving startup problems is more a matter of working through the different possibilities, one by one.

Understanding the Windows 98 Boot Process

Windows 98 goes through a series of steps as it boots the computer. If everything's working well, you won't care about the details about how Windows 98 gets the computer from an off state to when it displays the opening desktop. However, when troubleshooting boot problems, it's helpful to understand how booting works.

When a computer is powered up, the first thing that happens is that a program built into the computer's Basic Input/Output System (BIOS) runs and performs a Power-On Self Test (POST). The POST tests all the key system components to make sure that they're all there and that they're minimally functioning. Also, the RAM in the computer is briefly tested during the POST.

After the POST completes, the BIOS automatically loads a small program from the primary hard disk on the system (or from a disk drive, or in rare cases a CD-ROM). This small program is called a bootstrap because it helps the computer "pull itself up by its bootstraps." The bootstrap loads the operating system's own bootstrap program from special startup sectors on the hard disk and transfers control to the operating system. The operating system programs then proceed to initialize the hard disk's file system, and control is transferred to other programs, on down the line until the system is completely booted.

The first phase of Windows 98's startup process involves scanning the installed hardware in the system and selecting the appropriate Hardware Profile from the Registry. After the Hardware Profile is activated, Windows 98 processes any commands found first in the CONFIG.SYS file, and then the AUTOEXEC.BAT file, both located in the root directory of the primary boot device. that although CONFIG.SYS and AUTOEXEC.BAT are not required for Windows 98, they are still processed in case they are needed for compatibility with older software or hardware on the system. Any drivers loaded by CONFIG.SYS and AUTOEXEC.BAT are real-mode drivers; the operating system has not yet switched the system into protected mode.

Windows 98 then proceeds to load WIN.COM and any VxD device drivers needed for the system. There are both static VxDs that are loaded during each boot and dynamically loaded VxDs that may or may not be loaded, depending on the selected Hardware Profile. The individual VxD device drivers are all contained in a file called VMM32.VXD.

The VxDs that are part of VMM32.VXD are loaded based on entries found in the Registry at HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD. If there are conflicting entries in the SYSTEM.INI file, the entries in SYSTEM.INI will take precedence over the Registry entries.

After the VxDs are loaded, Windows 98 switches the computer into protected mode to proceed. The first thing that happens during this phase is that the Configuration Manager is loaded and started, which then queries all Plug and Play devices in the system; if the system's BIOS doesn't support Plug and Play, then the various buses in the system are scanned for installed devices. Based on the information gleaned from the Plug and Play queries or the bus scanning, dynamic protected-mode drivers are loaded for the installed devices. After the device drivers are loaded, any resource conflicts between the devices (such as IRQ assignments) are resolved by the Configuration Manager.

Next, a variety of files are loaded: KERNEL32.DLL and KRNL386.EXE (contain the basic components of Windows and the Windows device drivers, respectively), GDI.EXE and GDI32.EXE (handle the graphical interface duties for the operating system), and USER.EXE and USER32.EXE (provide the user-interface programming for Windows 98). Any related resources, such as icons, images, and fonts, are then loaded. Next, WIN.INI is processed and the desktop software is loaded and started. When User Profiles are active on the system, a logon prompt for the system then displays. After the user logs on, any settings specified for the User Profile are processed. Finally, any programs listed in the Startup folder are loaded for the user while the desktop initializes.

Windows 98 Startup Files

There are seven key files that form the base of Windows 98's startup behavior. They are all (except for WIN.INI and SYSTEM.INI) located in the root directory of the primary boot device, usually C:.

Understanding Startup Problems

If a Windows 98 computer won't boot, the trouble is most likely due to one of the following reasons:

You'll take different paths for resolving each of these errors. The following sections discuss each type of problem in more detail.

WARNING: This author can't count the number of times he's worked through a failure with someone, only to determine that the failure required a restoration of data from a backup, and then discovering from a panicked user that there are no backups--or only very old backups--available. The very best emergency recovery tool anyone can ever have is a current, reliable backup of the system. Computers can and do fail, and sometimes spectacularly. A good backup system in place will prevent you from losing thousands of hours of accumulated work that is irreplaceable. If you're in an environment that relies on users to perform their own backups, you owe it to them to hammer this point home as forcefully as you can. Even better, find a way to take backups out of their hands and set up a reliable system to take care of this necessary chore.

Resolving Hard Disk Problems

Hard disk drives are much more reliable than in years past. It used to be that they had a Mean Time Between Failure (MTBF) of about five to seven years. Now, most drives quote MTBFs of 20 years or more. Still, even with this increased reliability (or more optimistic marketing--we're not sure), hard drives can still fail. Sometimes they fail slowly, accumulating bad sectors at a gradual rate, which then accelerate over time, and sometimes fail suddenly, going dead for no apparent reason. The first order of business is to ascertain whether the hard disk has failed. Afterward, if you determine that the primary boot drive has indeed failed, you can take these steps to replace it and rebuild your system:

1. Leave the system powered on for an extended period (at least an hour) and then try to restart the system with a warm boot. If you can do this in a warm environment, it may help.
2. If the drive still isn't starting after going through this warm-up phase, try a cool-down phase and leave the system powered off overnight, and try it again first thing in the morning.
3. This is really a desperate move, but the author has seen it work before: Warm up the system for an hour by leaving it on, and then give the hard drive a couple of sturdy whacks with the heel of your hand, then do a warm boot. (Make sure you've tried everything else first, because this can damage the drive!)

If all the preceding steps fail, you've most likely got a failed primary drive on your hands. You'll need to replace it, reinstall Windows 98, reinstall all of your applications, and then restore your data from backup.

TIP: Most hard disk drives have at least a one-year warranty. If the drive has failed, you might be able to get a free replacement from the drive's manufacturer or your computer's manufacturer.

Assuming you are getting normal POST behavior from the drive (the hard disk lights flash normally during startup and normal sounds emanate from the drive), then you start to get into other configuration problem possibilities. Check the following:

1. Start the system with the EBD and see if you can do a DIR of your C: drive. If so, perform a SCANDISK on the C: drive, and then use the SYS command that is part of the EBD to reinstall the system files on the drive. Continue with the "Resolving System File Problems" section.
2. Start the system with the EBD and use FDISK to see if the disk partition data has been lost for some reason. You may be able to repartition the disk and have it start functioning again, with your data mostly intact. However, this requires that the partition be created exactly as it was when the system was last working, and this is a chancy proposition at best. Chances are you'll have to repartition the drive and reinstall Windows 98 and your applications.

Resolving Other Hardware Problems

Sometimes a system won't boot and the problem isn't due to the hard disk drive. It might be due to another device in the system that's failing in some way and preventing a startup, or it may be a number of different possible file problems. This section deals with the former possibility, while the next two deal with the latter.

If the system starts to boot, displays the message Loading Windows 98 and possibly the Windows 98 splash screen, but then stops booting, try these steps to find out if there's other hardware in the system preventing startup:

If the above ideas and the previous section fail to get Windows 98 started for you, then you're most likely suffering from a problem with one or more system files that are corrupt or missing. Proceed to the next section to deal with those problems.

Resolving System File Problems

Windows 98 processes many files in order to boot properly and display the desktop. If one or more of the critical files are damaged or missing, the system may not be able to boot or recover from the problem. Follow these steps to diagnose and resolve these problems:

1. SCANREG checks the system Registry for problems. Type SCANREG /? for different command-line options for fixing the Registry and restoring a previous backup of the Registry.
2. SCANDISK checks the system drive for errors, both in the directory structure and throughout the surface of the disk.
3. Run System Information (from the Start menu, Programs, Accessories, System Tools menu). Scan its information tree for clues indicating a problem, and run additional tools from its Tools menu as indicated in the following steps.
4. Run System File Checker from System Information, which examines all the Windows 98 files and automatically reloads any corrupt or incorrect files from the Windows 98 CD-ROM.
5. Run Dr. Watson from System Information, which causes the Dr. Watson icon to appear on the TaskBar. Click the icon and then choose Dr. Watson from the pop-up menu. The Dr. Watson program scans the system and reports any errors it finds.
6. Run System Configuration Utility (described in the next section) to enable special startup features that may let you isolate a specific startup troublespot.

Basically, if you've eliminated hardware as a boot failure cause, and you've eliminated other hardware or disk configuration as a cause, your primary goal is to boot the system in either Safe Mode or with the EBD, and then replace any known bad files or simply reinstall Windows 98 from your CD-ROM. After working through this section and the previous two sections, you should have a system that boots, and can then proceed to more detailed troubleshooting if necessary, as discussed in Chapter 37.

Troubleshooting Startup Problems with System Configuration Utility

Windows 98 includes a tool called System Configuration Utility that lets you selectively enable and disable certain startup parameters. System Configuration Utility replaces SYSEDIT.EXE, and is a much more powerful utility for controlling the Windows 98 startup files. You can start it by using the Run command from the Startup menu and then typing MSCONFIG. You can also access it from the Tools menu of the System Information Utility.

To use System Configuration Utility, you must be able to start the system in some fashion, even if only in Safe Mode. You can then use the settings in System Configuration Utility to try to isolate the problem. System Configuration Utility is shown in Figure 36.1.

Figure 36.1

System Configuration Utility's General tab.

The General tab lets you choose how Windows 98 will boot next. You can choose from the following three choices:

If the system boots in Safe Mode but not normally, use the Selective Startup option to disable elements that you think may be related to the startup problem, such as CONFIG.SYS, AUTOEXEC.BAT, WIN.INI, or SYSTEM.INI. If this fails to resolve the problem, choosing Diagnostic Startup gives you a few more choices during the startup.

Click the Advanced button in the General tab to bring up the Advanced Troubleshooting Settings dialog box shown in Figure 36.2. Here you can choose even more settings that may help you diagnose and solve the startup problem, as described in Table 36.1.

Figure 36.2

Advanced Troubleshooting Settings dialog box.

Table 36.1 Advanced Troubleshooting Settings

Setting Description
Disable System ROM Forces Windows to avoid using the first 1 MB of memory
Breakpoint for the system ROM breakpoint
Disable Virtual HD IRQ Disables the Windows code BIOS routines for handling hard disk IRQ signals that handles IRQ signals for the hard disk and instead forces the system to use the ROM
EMM Exclude A000-FFFF Forces Windows to avoid using the area traditionally set aside for EMM memory
Force Compatibility Bypasses protected mode support for disk
Mode Disk Access access and instead routes disk access through real mode
VGA 640*480*16 Forces the system to start in basic VGA display mode
Use SCSI Double-buffering Causes the system to use SCSI double-buffering, which may resolve SCSI I/O problems; setting can also be forced through MSDOS.SYS
Enable Startup Menu Forces the Windows Startup menu to appear without having to hold down the Ctrl key during boot
Disable Scandisk After Bypasses the automatic SCANDISK after the system was
Bad Shutdown not shut down gracefully
Limit Memory To Limits the addressable system RAM to the amount specified, which can be useful for diagnosing suspected RAM problems
Disable Fast Shutdown Disables the shutdown performance enhancements; for use if Windows 98 is having trouble shutting down properly
Disable UDF File System Disables support for Universal Disk Format; for use only when troubleshooting DVD players
Enable Pentium F0 Bug For Pentiums at the F0 revision level, turns off alternate
Workaround code that attempts to handle a bug on the processor

The remaining tabs in the System Configuration Utility all work the same way: They display the various settings associated with the tab's file, and let you selectively activate or deactivate those settings. Figure 36.3 shows the CONFIG.SYS tab; the others also offer listings with checkboxes for enabling or disabling specific settings.

Figure 36.3

System Configuration Utility's config.sys tab.

Understanding the Windows
Startup Menu

Windows 98 lets you access a Windows Startup menu that enables you to try to start the system in various ways from the primary boot partition. Under Windows 95 you accessed the startup menu by pressing the F8 key when the message Loading Windows 95 appeared. Under Windows 98 you instead hold down the left Ctrl key while the system starts. You then see the Windows Startup menu, which lets you choose from the following options:

If a system is having trouble starting, first try to start the system in Safe Mode. If that fails to start the system, try both Command Prompt Only and Safe Mode Command Prompt Only to try to get to a command prompt. If you cannot get to a command prompt using these methods, you'll have to use the EBD, discussed in the next section.

Understanding, Preparing, and Using an Emergency Boot Disk

When you install Windows 98, and whenever you make major configuration changes to the system, you should prepare a Windows 98 Emergency Boot Disk (EBD). The EBD is a boot disk that starts the system without accessing any files stored on the hard drives, and gives you a command prompt along with the most common utilities needed to resolve emergency boot problems. The EBD has been significantly enhanced in Windows 98 over the one used with Windows 95.

WARNING: Do not attempt to use a Windows 95 EBD to recover a Windows 98 system. You must use a Windows 98 EBD.

The EBD boots the system and creates a 2MB RAM disk, onto which it places the key utilities you may need to repair a system. When you boot a system with its EBD, you see a menu with three choices:

Generally you will choose to start the system with CD-ROM support. There are general-purpose CD-ROM drivers on the EBD that can initialize most IDE- and SCSI-based CD-ROM drives. If you cannot access your CD-ROM drive after starting the EBD in this mode, you'll have to modify the EBD's CONFIG.SYS and AUTOEXEC.BAT file to use the appropriate drivers for your system's CD-ROM (see Chapter 2, "Installing Windows 98"). You want CD-ROM support so that you can replace corrupted Windows system files or reinstall Windows 98 from the CD-ROM.

Preparing the EBD

To prepare the EBD, you'll need a 1.44MB disk that contains no bad sectors. Start by opening the Add/Remove Programs Control Panel, and then move to the Startup Disk tab shown in Figure 36.4. Click the Create Disk button to build the EBD disk.

Figure 36.4

Add/Remove Program's Startup Disk tab.

TIP: It's a good idea to test the EBD by trying to boot the system with it after you've prepared it. Waiting until the system fails to boot is no time to find that your EBD doesn't work for some reason!

You should update the EBD whenever you make major configuration changes to the system, such as adding or removing hard disk drives or CD-ROM drives. However, the EBD has been designed to be as general as possible, and you can often use another computer's EBD to boot a similar system (as long as the EBD you use was created from a Windows 98 system).

Understanding the EBD

The EBD boots the Windows 98 version of MS-DOS, and then creates a 2MB RAM drive to hold the EBD utilities. The utilities are automatically copied to the RAM drive. The RAM drive is created using the first drive letter that follows any hard drives defined in the system, but before the CD-ROM drive letter. Your CD-ROM drive letter will therefore be moved up one letter when booting from the EBD.

The EBD utilities are stored in a file called EBD.CAB on the EBD disk. EBD.CAB is a compressed file that is automatically decompressed to the created RAM drive as the EBD boots. Table 36.2 details the EBD utilities contained in the EBD.CAB file.

Table 36.2 EBD Utilities

Utility Name Purpose
ATTRIB.EXE Utility that lets you set file attributes; you may use this to remove a file's hidden or read-only attributes prior to replacement, for instance.
CHKDSK.EXE Abbreviated version of SCANDISK that checks a drive's directory structure for errors.
DEBUG.EXE MS-DOS debugger, which lets you perform byte-level patching of files.
EDIT.EXE Simple text editing program for making changes to system text files, such as CONFIG.SYS or AUTOEXEC.BAT.
EXT.EXE New file extraction utility that makes it easy to search the Windows 98 .CAB files on the CD-ROM for individual files and extract those files to a destination of your choice.
FORMAT.COM Utility to format disks.
MSCDEX.EXE CD-ROM extensions for MS-DOS.
SCANDISK.EXE Comprehensive disk testing tool; checks both directory structures and can perform surface analyses.
SCANDISK.INI Configuration file for SCANDISK.EXE.
SYS.COM Utility that places system boot files onto a disk.
UNINSTAL.EXE Utility that uninstalls Windows 98.

Using the EBD

After you have booted a system with the EBD, you'll want to follow certain steps to resolve most startup problems. First, you should run SCANDISK on the boot drive, drive C:. Any errors in the directory structure that are keeping the system from starting should be resolved by SCANDISK. Take careful note of any files that SCANDISK indicates are damaged (contain bad sectors, are cross-linked, or have other problems); you should replace them from the Windows 98 CD-ROM after SCANDISK repairs the problems on the disk.

If a few damaged files were indicated by SCANDISK, then use the EXT utility to extract fresh copies of those files from the Windows 98 CD-ROM. Simply type EXT from the RAM disk command prompt, and then indicate what file you want to replace, where the Windows 98 .CAB files are located (usually x:\WIN98 where x: is your CD-ROM drive letter), and where you want the extracted file to be placed (usually either C:\WINDOWS, C:\WINDOWS\SYSTEM, or C:\WINDOWS\SYSTEM32 as appropriate for the file).

If there appear to be many damaged files, and you think that any bad sectors on the hard disk were fully repaired by SCANDISK, you should run Windows Setup from the Windows 98 CD-ROM to reinstall all the Windows 98 files. Also, if all else fails, go ahead and try to reinstall Windows 98 using this method; many problems will be automatically resolved by reinstalling the operating system. You shouldn't lose your Windows settings by doing this.

If none of the preceding suggestions work and Windows 98 still won't boot, you're certain that the hard disks in the system are fine, and that there aren't other hardware problems causing Windows to fail to boot, try this last resort: Use the UNINSTAL utility in the EBD to remove Windows 98, and then reinstall Windows 98 from scratch. You will lose your Windows 98 settings, and will have to reinstall your applications.

Conclusion

Solving startup problems can be frustrating and challenging. Fortunately, there are some powerful tools that let you access a Windows 98 computer without needing Windows 98 itself, such as various Windows Startup menu options and the Windows EBD. By using such tools, along with other emergency troubleshooting tools discussed in this chapter, you should be able to recover from any such emergency.

The next chapter, "Tools and Strategies for Troubleshooting Windows 98" continues the troubleshooting topic with specific advice on troubleshooting various possible problems, along with coverage for the troubleshooting tools included in Windows 98.

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