Some websites are block by proxy. How can I by pass proxy?

Use VPN.
Only important to use proven services, such as this one: https://boxpn.com/ - connect to OpenVPN protocol and can be calm about your information.
Not worth it, by the way, to use Free VPN - free cheese is only in a mousetrap.
Boxpn mentioned because I use and quite happy.

You should have extra rules that permit ICMP or exchange emails. Require would be the important guidelines regarding proxy browsing. Now your own users will possibly use the proxy server to surf the web or simply get absolutely no connections. Mix this along with authentication and you also finally possess control as to what the work stations do. This is simply not just useful your users or even lurk the way they are browsing but rather maintain simple spyware aside that either will not understand how to make use of a proxy or even don't have the actual account information required to sign in.
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It is easy to access blockes websites with VPN service. It is safe and secure and always helps.

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