Diagnosing Issues in Windows Vista (part 4) - Troubleshooting Startup Problems

Troubleshooting Startup Problems

When the Windows Vista operating system encounters problems during the startup process, the symptoms are usually apparent. The system might not display a startup screen at all, or a startup screen is shown, but the computer does not boot to a logon screen or the Windows desktop. In some cases, the computer might spontaneously reboot during the startup operation. Regardless of the symptoms, the goal is to enable Windows Vista to boot normally again.

The most frustrating part of troubleshooting startup problems is that there is generally no available operating system with which to interact. Without the Windows Vista user interface, it’s not possible to launch standard graphical programs. To assist in troubleshooting these problems, Windows Vista includes numerous startup modes that you can use to try to regain access to the system. Users can access the Advanced Boot Options menu during the startup process by pressing F8. Figure 12 shows the available options.

Figure 12. Viewing Advanced Boot Options for Windows Vista

Each option has its own particular purpose for resolving a potential problem. Table 1 provides a listing of each option and its associated description.

The descriptions provide an overview of the type of startup option. In this section, you’ll learn how you can use the various options to troubleshoot common problems.

Understanding Safe Mode

The most common types of problems that can prevent Windows Vista from starting up normally include the installation of new device drivers or system-related applications or services. If these programs are incorrectly configured or are of poor quality, they can cause the startup process to fail entirely. To help troubleshoot these problems, Windows Vista includes a Safe Mode feature.

When booted in Safe Mode, the operating system startup process loads only a minimal set of device drivers and settings. It also enables various other troubleshooting features. For example, Figure 13 shows how the startup process displays a list of drivers and Windows-related files that are automatically loaded.

Figure 13. Viewing a list of device drivers when performing a Safe Mode startup

The goal of Safe Mode is to prevent device drivers and other software from interfering with the startup process. For example, because only basic display adapter drivers are loaded, you can use Safe Mode to avoid common problems caused by video drivers. There is, however, an associated disadvantage: some operating system features and functionality are unavailable in Safe Mode. The most noticeable difference is that the screen resolution and color depth are usually set to low values, and the system might appear to be operating much more slowly than normal. Figure 14 shows an example of logging on to Windows Vista while running in Safe Mode. Note that the words “Safe Mode” are displayed in the corners of the screen, and then a Windows Help And Support window automatically opens.

Figure 14. Running Windows Vista in Safe Mode

In addition to the standard Safe Mode boot options, users can choose from related options. Safe Mode with Networking loads a minimal set of drivers but also loads network drivers. This option is helpful because it allows troubleshooters to connect to the Internet to obtain updated drivers or more information about the problem. The Safe Mode with Command Prompt option automatically launches the command window for performing text-based operations. This option is most appropriate when system problems are preventing Windows Explorer from properly starting.

Safe Mode is intended to be a temporary startup option designed to perform troubleshooting. Common operations might include uninstalling new software or removing or disabling hardware devices. After the troubleshooting process completes, users should choose to restart the computer. On the next boot operation, Windows Vista automatically attempts to perform a normal boot.

Using Windows Error Recovery

Startup problems can occur due to a variety of different problems on the system. In some cases, the addition of new hardware or faulty device drivers might prevent the computer from starting up normally. In other cases, a hardware failure or corruption of boot-related files might have occurred. It’s also possible that there was a temporary problem, such as a power failure.

Windows Vista is able to detect startup-related failures automatically. If the operating system failed to boot successfully during its last attempt, the boot manager automatically displays the Windows Error Recovery screen (see Figure 15).

Figure 15. Using the Windows Error Recovery screen during the boot process

This screen informs the user that there was a potential problem with startup and that there might be a hardware-related error. The available boot options include the following:

• Safe Mode

• Safe Mode With Networking

• Safe Mode With Command Prompt

• Last Known Good Configuration (Advanced)

• Start Windows Normally

Although it is certainly possible that a hardware-related issue might require restarting the computer by using the installation disc or by using one of the other options, it is also possible that a simple power failure caused the screen to appear. Therefore, it is generally a good idea to try using the Start Windows Normally option unless the problem occurs repeatedly.

Using Boot Logging

One potentially challenging aspect of troubleshooting startup problems is identifying the source of the startup problem. Windows Vista loads dozens of drivers and services during a typical startup process, but which one is causing the problem? The purpose of the Boot Logging startup option is to instruct Windows Vista to create a text file automatically that contains a list of the operations it performs during the boot process. To enable boot logging, during the startup process, from the Advanced Boot Options menu, select Enable Boot Logging. Generally, the last item in the list is the source of the startup problem.

The log file itself is a text file named Ntbtlog.txt located within the Windows folder (usually C:\Windows), which you can open using Notepad or command-line utilities such as Type. Figure 16 shows an example of the information that you can find in the file.

Figure 16. Viewing the contents of the Ntbtlog.txt file

Using the Last Known Good Configuration

Sometimes, when performing troubleshooting operations, you might find yourself wishing for a way to revert the system configuration automatically to a previous state. That’s the purpose of the Last Known Good Configuration startup option on the Windows Error Recovery screen. When Windows Vista successfully completes a boot operation, it makes a backup of the important startup-related files and settings. If a problem occurs during the startup process, the system can use the previous “known good” set of startup files.

Although this option can simplify troubleshooting, there is a potential drawback to consider: if new applications were installed or system settings were recently modified, it’s likely that other system problems might occur. For example, if a newly installed application required system Registry changes to occur, it might not run properly when reverted to an older configuration. In this case, it might be necessary to reinstall the program. Because of these potential issues, the Last Known Good Configuration boot option is considered an advanced process and is not recommended as an initial troubleshooting step.

Configuring Startup Options with MSConfig

In some cases, the Windows operating system might boot properly, but you want to change the way in which the system starts up the next time you restart it. You can use the System Configuration (MSConfig) utility to specify various startup options. Figure 17 shows the General tab of the System Configuration dialog box.

Figure 17. Viewing the General tab of the System Configuration dialog box

The Startup Selection options include the ability to specify Normal Startup (the default option) or to perform a Diagnostic Startup. The latter option specifies that the computer should run with a minimal set of devices and services. It is useful when trying to resolve issues that might have been caused by the installation of new software or devices to the system. The last option, Selective Startup, offers the ability to enable or disable the following boot operations:

• Load System Services

• Load Startup Items

• Use Original Boot Configuration

When you select modified startup options, Windows Vista informs the user of this during the next boot of the computer. Users can then return to the MSConfig utility to make changes to the computer’s startup configuration. Generally, you should use these settings only when troubleshooting a specific problem. It is not recommended that computers run using modified startup operations for general use because certain operating system features and applications might fail to work properly.

In addition to the settings on the General tab, the System Configuration dialog box includes a set of startup options on the Boot tab (see Figure 18). These options enable users to specify which mode Windows Vista should use when they restart the system. For example, you can select the Safe Boot check box to boot the system into Safe Mode automatically without requiring input from the user.

Figure 18. The Boot tab of the System Configuration utility