Thanks to two tools that ship with Windows 2000, we now have more options when troubleshooting computer boot problems. If you have Windows 9x experience, you're probably familiar with the first tool, Safe Mode. The second, the Recovery Console (RC), is new to the Microsoft product line. This week, I discuss these tools and explain how you can use them to fix a system that won't start.
To enter Safe Mode, press F8 early in the boot process, before the Win2K startup screen appears. On a dual-boot machine, you can press F8 when the boot menu appears. After you press F8, the Advanced Options menu appears and offers you three Safe Mode level choices. The first, Safe Mode, attempts to load the OS with only the drivers and services it needs to start the computer for basic operations. The second, Safe Mode with Networking, adds the network card drivers and the services required for networking, such as the server and workstation services. The third, Safe Mode with Command Prompt, doesn’t load the GUI, explore.exe, but instead brings you to a command prompt. To see the exact list of drivers and services that each mode loads on your machine, look at the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Safeboot registry subkey.
Safe Mode is a great tool to turn to if you load an application or add a device and the system hangs when you try to reboot. Safe Mode loads only the drivers you need to boot the OS so that you can load a new driver or uninstall the offending application or service to fix the problem. Like Windows NT 4.0, Win2K gives you the Last Known Good Configuration option, so you can boot to Safe Mode and address the problem without losing configuration changes that have occurred since the last successful system start.
The Recovery Console
The RC is useful when the system doesn't boot successfully using Safe Mode and Last Known Good Configuration—a situation that might arise if critical system files are deleted or become corrupted. The RC gives you command-line access to the root folder, the %systemroot% folder, and removable media drives such as the disk drive and the CD-ROM drive. With the RC, you can use a limited set of commands to perform functions such as copying files from a CD-ROM to the hard disk, enabling or disabling services, and repairing the Master Boot Record (MBR). For a complete list of RC commands, check out Microsoft article Q254582.
You can access the RC in two ways. You can boot the computer from the Win2K installation CD-ROM and choose Repair a Windows 2000 Installation from the Welcome to Setup dialog box. You can also copy the RC files to your hard disk using the winnt32.exe /cmdcons switch, which adds the RC to the list of available OSs on your boot menu.
By default, when you use the RC, your access is limited to the removable media that I mentioned earlier. Group Policy security setting control this access. Two settings let you control RC functionality: Recovery Console: Allow automatic administrative logon and Recovery Console: Allow floppy copy and access to all drives and all folders. You can use these settings to increase RC functionality, but doing so can create security vulnerabilities.
Put Safe Mode and the RC to work for you the next time you have to troubleshoot a Win2K machine that won't boot. These tools can save you some time and ease an often stressful predicament.