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I want to be able to connect to a wireless router without the risk of malware infecting my computer or anyone reading/changing my files.
This might be in a public place like a café or an airport, or at someone's house where security is not their top priority. (I'm using Windows 7.)
This is not a question about security or privacy threats through the internet, such as visiting a site with a drive-by virus or someone intercepting passwords typed in a web browser.