Read this advisory if you are not sure why you would want to move from WEP to WPA.
To do this, you’ll need to change the configuration on your wireless access point (which may be the same device as your broadband router), as well as every computer that access the Internet – wirelessly – through that access point.
Find your brand of wireless access point below:
If you have a link or a procedure and you want it listed here, contact me. I’ll even give you credit! Or, put your link/procedure in the comment fields below.
Find your version of Windows below:
Microsoft Windows Vista (sorry, I can’t find a decent page on Microsoft.com)
Peter H. Gregory 
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What about windows 7?
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