Hi Wayne and welcome to the WTT forums, Sorry to hear about the wireless issue.
There could be a number of reasons for this so we need to try and zoom in on the most likely areas by the elimination of some factors...but before we start, its worth saying that some problems arise when folks find that the software provided by the wireless adapter manufacturer tries to manage the wireless connection whilst Windows is trying to manage it at the same time....
The result is no wireless connection...
1 For the purposes here, try and let Windows manage the connection using Windows Zero Configuration as this may be all that is required... if still no joy, then power cycle the modem, wait 3 minutes, power cycle the router/wireless access point, wait 3 minutes, (if he is using one) then reboot the computer and see if you can connect.
2 If still no joy and to figure out if its the settings on his computer, a computer hardware failure or a modem/router wireless access point issue, try this:
A Use a known good computer that can use wireless with no problems and see if you can connect wirelessly to his router (wireless access point) does it connect to the Internet OK...?. if it does then it means that the modem/router/wireless access point are working OK.... so we need to concentrate on the computer itself.
B As an extra check try and connect his computer to someone elses Internet by wireless (obviously with their permission) if it doesn't connect ( despite using the correct encryption key (he will need to ask for it) then its pointing to his computer as the culprit.
Try and make sure when this is tested that the computer is within about 6 to 10 feet of the wireless access point/router being used for the test.
3 Back at his home try to connect again via wireless but with encryption switched off but with the SSID still being broadcast (you will need to go into the Router/wireless access point settings for this)
4 If you still have no joy then try this:
With Ethernet cable disconnected and wireless network adapter enabled
5 Click on Start
6 Click on Run
7 copy and paste into the white box the following command:
cmd /c "ipconfig /all > postme.txt & ping bbc.co.uk >> postme.txt & notepad postme.txt & del postme.txt"
Click on OK
Note the quotes..they need to be there...
Copy the output and then post it into your reply here, and one of us will advise the next steps