The term zero configuratfion implies an easy setup, but with Windows XP's Wireless Zero Configuration (WZC) service, that frequently isn't the case.
The problem: From time to time, when you insert your card (or power up), XP won't let you connect to a network. As shown in figure 1 below, the most common symptom is that the Connect button in the networking dialog box is "greyed out," unavailable for use. To complicate matters, the card will even flash its LEDs and appear to be installed properly in the Device Manager.
In some setups, this glitch arises every other time you reboot; in others, it's only every fifth or sixth time. Some people never see the problem at all, but whenever it happens, it's a major nuisance.
On discussion forums, some - but not all - users report that installing the Wireless Update Rollup Package from Microsoft may fix this particular Wi-Fi annoyance.
You may already have installed this rollup (released in October 2003) via Windows Update. To find out, click Start, Windows Update, then click View Installation History in the left pane. Look for an entry named 'Update for Microsoft Windows XP (KB826942)'. If it's present, you have the rollup installed.
If you have the patch, and the connection problem persists, try stopping and then restarting the Wireless Zero Configuration service. This forces Windows XP to reset the card's drivers, which should snap to attention immediately afterward.
To start this procedure, you must open the Services console: Right-click My Computer on the Desktop, and select Manage. In the management console, click the plus sign next to the Services and Applications item in the left pane, then click Services. Scroll down and double-click Wireless Zero Configuration in the right pane.
Unless you had previously shut off the service, the dialog box will report the service's status as Started, and the Stop button will be active. Click Stop, wait a moment, and then click the Start button when it becomes active. If this fixes the problem, you'll likely have to repeat the process each time you encounter the same set of symptoms. (See Fig 2)
If restarting the service doesn't fix the problem, you may need to update firmware in your Wi-Fi card, or update your Wi-Fi card drivers to versions that have been certified for Windows XP. In a worst-case scenario, where WZC fails more often than it works, use the instructions above to stop the service, and then just use the software that came with your card to set up a connection to your LAN.
Fig 1 XP's Wi-Fi bugs can grey out your buttons
Fig 2 A quick restart of WZC service can get XP on the Wi-Fi track