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What's Wrong With My Network?

Can your PC or peripheral see the network? If your broadband connection isn't working--DSL or cable modems sometimes lose their connection, causing a dead Internet link--power-cycling the modem usually solves the problem. Turn the device off or unplug it from the power outlet, and then turn it back on. Do you have networking hardware, such as a router or hub, that's connected to the modem? If so, power-cycle that device as well--but only after you power-cycle the modem.

Is your networked printer not working? First, make sure you have shared the printer. Go to Start, Control Panel (or in Category view click Start, Control Panel, Printers and Other Hardware) and select Printers and Faxes. Right-click the printer you want to share, then click Sharing. On the Sharing tab, click Share Name and type the printer's name. Another possible explanation: The printer is connected to one network-connected PC, which is turned off. The obvious solution is to leave that computer on at all times. Or reduce your energy bill and buy a print server ($30 to $50) that connects the printer directly to the network. See "How Do I Share a Printer on My Small Network?" for more info.

Is your PC's connection to the network balky? If the network is too slow, or has stopped working altogether, first try running the Windows XP network troubleshooting feature. Go to Start, Help and Support, and under 'Pick a Help topic' click Networking and the Web, then select Fixing network or Web problems, and finally choose Home and Small Office Networking Troubleshooter. The troubleshooter asks you a series of questions to help pinpoint the problem, and as you drill deeper the troubleshooter will run a diagnostic program to try to locate the source of the difficulty. Unfortunately, the tool rarely discovers anything you couldn't have figured out yourself, but it's still worthwhile to use as a starting point, just to make sure you haven't overlooked anything obvious.

Does your laptop take several attempts to connect to your Wi-Fi router? First, check to make sure your network isn't clogged with other data. Do you have any devices connected to your network that are streaming music or video from one part of the house to another? Such activity could cause a delay in your notebook's getting connected, which you can test for by turning off the streaming-media device temporarily. RF (radio frequency) interference might also be to blame; a utility called NetStumbler can help you diagnose the problem. The software (see "Troubleshoot Wi-Fi With NetStumbler") checks for sources of signal interference, which could simply be a nearby household appliance such as a microwave oven or a cordless phone. NetStumbler also scans for other wireless LANs in your area, which could be using the same router channel as you. The 2.4-GHz range has three nonconflicting channels--1, 6, and 11--and you'll want to pick the least crowded channel of those three. In addition, check your laptop's wireless signal strength. (Wi-Fi cards typically place an icon depicting signal strength in the system tray.) If possible, move the portable closer to the wireless transmitter for a stronger signal. A weak signal may be the result of obstructions in your home. Lincoln Spector offers more troubleshooting advice in his January Answer Line column.

Does your Wi-Fi connection seem slower? Your neighbors may be piggybacking on your network and using your Internet pipe without your consent. The solution: Activate the Wi-Fi gateway's security. This involves several tasks, including changing the gateway's vendor-supplied default password and enabling WPA Pre-Shared Key encryption. These security steps vary by hardware vendor; you'll find good instructions for most popular gateways at GetNetWise. You might also update the security options available by upgrading the firmware in your wireless devices; see Andrew Brandt's MarchWireless Tips for help.

Is your firewall causing conflicts? Software firewalls sometimes will block a program you want to use to access the Internet. You may have accidentally clicked 'Keep blocking this program' (in Windows Firewall) or 'Block' (if you use the ZoneAlarm software firewall) rather than 'Unblock the program' or 'Allow' the first time the application ran.

To correct this in Windows Firewall, select Start, Run, type wscui.cpl In the Open dialog box, and click OK. Click Windows Firewall, choose the Exceptions tab, and then click Add Programs. Select the app you wish to unblock from the list, or click Browse to locate it.

To fix the problem in ZoneAlarm, double-click the ZA icon in the system tray, click Program Control on the left side of the window, and click the Programs tab. Scroll down the list until you see the program you want to use, and if you see any red X icons next to it, click the icon and choose Allow from the drop-down menu.