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VPNs bypass Netflix's geo-restrictions by masking the user's IP address. Netflix knows about VPNs and doesn't want the viewers to use them. VPNs help users mask their IP address by assigning them with the server's IP. Netflix has agreements with other companies that don't allow streaming shows and films in regions where Netflix isn't licensed to distribute them. It's not illegal to use a VPN to watch Netflix with a VPN, as long as you live in a country where VPNs are controlled by the law.