Back Up Critical System Files

Several of the tips here require modifying the Registry. Be very careful! Tampering with system files can cause problems if not done properly. To be safe, back up the Registry and other critical files before making any changes.

Microsoft makes this easy. Just select Start and click Programs in Win Me or All Programs in Win XP. Select Accessories and System Tools and System Restore. Choose Create a restore point and Next. Give the restore point a description, and press Next in Win Me or Create in Win XP.

If your system develops any problems and you can still get into Windows, follow these steps to get back to System Restore, and choose Restore my computer to an earlier time. If Windows will not boot, press F8 as soon as the operating system starts trying to load. If you're running Win Me, boot to Safe Mode and run System Restore. In Windows XP, you can use Safe Mode or choose Last Known Good Configuration.

Back Up Your Media Licenses

If you do choose to copy-protect your files, you need to preserve a copy of your media licenses in case you ever need to reinstall Windows XP. To export the key from your existing Windows XP machine, open Media Player, select Tools | License Management, and click Backup Now.

The licenses will be copied to the desktop as files with .bak extensions. Note that they may be hidden if you don't allow Explorer to show hidden files. To import them, place the files on the desktop and click Restore Now.

Beef Up Mobile Security

Being mobile exposes you to additional dangers, especially if you use wireless networking. Here are some pointers for improving your security.

• In the Control Panel's Power Options menu, go to the Advanced tab and check on the box Prompt for password when computer resumes from standby.
• Use a firewall (see the "Networking" section in this story).
• Be cautious about enabling file and print sharing, especially if you have wireless networking turned on. You can control sharing on a drive-by-drive or even folder-by-folder basis (Start | My Computer, then right-click on a drive or folder and select Properties | Sharing) or by user (look for and click on your user name in C:\documents and settings to access file sharing).
• Turn off wireless networking if you're not using it. Go to the tool tray in the lower-right corner of the screen. If there's a LAN (Wireless) icon, right-click on it and choose Disable. This gains you an extra 10 to 20 minutes of battery life.

Block access to Web sites with the Route command

If there are specific Web sites you want to prevent users from accessing, you could use Internet Explorer's Content Advisor or invest in a third-party solution to block access. But you can also block access to specific Web sites using the Route command to modify the route table.

When you type an Internet address into the browser, Windows XP uses the local route table as a network map to determine where to send the packet. In most cases, the route table directs the packet to the gateway, which then sends it out to the Internet.

However, you can configure the route table to send packets addressed to a certain Web site to a dead end. The result makes it appear as if the site doesn't exist.

To begin, you need the IP address of the Web site to which you want to block access. You also need an unassigned IP address within your local subnet that isn't in use by any computer or device.

For example, let's say that the IP address you want to block is 100.100.100.100, and an IP address on your local subnet that isn't in use is 192.168.100.51. Modify the route table with the following command:

Route -p add 100.100.100.100 mask 255.255.255.255 192.168.100.51

For more information on the Route command, check out the Windows XP Help and Support Center.

Boot Logger

Years of PC repair work can definitely take its toll on a person. I know a guy that has been known to "gently encourage" troubled PCs with the assistance of a tire iron from time to time. (Only did this with his own, never a client's... that would be very BAD). Sure, his neighbors think he is insane, but what do they know? Most of them resemble giant crickets that are trying to burrow into his brain anyway, so he tends to take their comments with a grain of salt.

I believe that his insanity stems from troubleshooting the hard way, rather than the smart way. As most of us without hallucinations know, Windows XP comes with a variety of tools built into the OS to help with troubleshooting common problems.

One such tool is called the boot logger. When dealing with bootup problems that have you stumped, this tool is invaluable. By creating a text log of the boot up process, you can quickly tell where the problem is coming from.

Let's get started, shall we?

1. You will need to restart the troubled computer running Windows XP.

2. Just before XP starts to load, press F8 as if you were trying to get into safe mode.

3. Select Enable Boot Logging option, and then press enter.

4. Now for the moment of truth. After the system's bootup process is finished, navigate over to the C:\Windows\Ntbtlog.txt file. There you will find a list of all of the drivers that did or tried to load during the boot process. By examining this file closely, you can quickly spot which service or driver is causing the problem.

Break out of a continuous reboot loop

Have you ever had to troubleshoot a Windows XP system that appeared to be stuck in a continuous reboot loop? In this scenario, you can start the system as you normally would and even log on. But within seconds of logging on, the system mysteriously reboots itself. In some cases, you don't even have to log on before the system reboots.

If this sounds familiar, you're encountering a feature of Windows XP's Startup and Recovery system. By default, this system specifically configures Windows XP to automatically restart itself after encountering a system failure error.

These system failure errors are usually isolated and occur randomly. As such, the best way for the operating system to deal with them is to automatically restart.

In most cases, doing so solves the problem. But if the system failure error is more serious and occurs on a regular basis, you'll encounter a continuous reboot loop.

However, you can disable the automatic restart behavior. Follow these steps:

1. Press [Windows][Break] to open the System Properties dialog box.

2. On the Advanced tab, click the Settings button in the Startup And Recovery section.

3. In the System Failure section, deselect the Automatically Restart check box, and click OK.

4. To enable the changes, click OK in the System Properties dialog box.

Keep in mind that you'll have to work fast in order to make the change before the system reboots. You may have better luck making the change if you launch the system in Safe Mode.

Bridge together two network segments

Windows XP ships with a feature that allows you to join two or more network segments that use different physical mediums to act like a single network. For example, you can use a bridge to tie an Ethernet LAN segment to a wireless network.

Follow these steps to create a bridge:

1. Install and setup all the network interfaces on your bridge computer. This computer needs to have two or more installed network interface cards (NICs) that will act as a software bridge.

2. Make sure all the NICs work and that there are no errors.

3. Open the Network Connections folder.

4. Hold the [Ctrl] key and select the interfaces that represent the network segments that you want to bridge or join together.

5. Right-click the chosen interfaces and select Bridge Connections.

6. After the configuration is complete, you'll see a Network Bridge icon in the Network Connections folder. This is where you can change the bridge's configuration settings.

Bridging is especially useful in small home and office networks. However, if you have a lot of computers and considerable traffic between them, you'll probably want to use a router. With a router, the networks will act like different segments and won't join with a bridge, but the computers will still be able to communicate.