How to can I open the Facebook or Gmail website when it is blocked by a firewall at an office?
You can try using https://www.terasurf.com I use it to unblock sites such as Facebook, and to watch movies and shows that are blocked in the countries I travel to.
Or you can work from home...
you can ask your network admin to open them for you, or you can look at them when you get home.
Forget about it. If it was blocked and you're in an office it's for a reason: there is a lot of them but the mains are: so you can concentrate on your work and to avoir viruses. So I think trying to access these website will be breaking the policy and you know what happen to people who does it...
Normally, I'd supply you with a short list of reliable proxies, but it looks like your job might restrict facebook and gmail access for a reason, so if I were you, I'd just bite the bullet and be socially 'disconnected' for a few hours a day (think of it as a blessing).
Generally the sideways (i.e. proxies) are also blocked where social sites are blocked. You can't find an easy way to bypass that, even if you do and it's recognized by your network administrators (internet logs, proxy logs and routine reports from the internet provider can be used to detect who accessed where). I don't advise to try to bypass them. Your best option is to use your private mobile devices (phone and tablets) for this.
Rather than risk getting fired, why not talk to who ever is in charge of IT at your place of employment.
If the website were blocked by the proxy firewall. then it is illegal to use these sites from office computer.
If you want to take risk then install spot flux you will be able to surf any site
use proxy sites like 4everproxy.com but be careful you might get fired. good not to use it.
it's illegal in some environments! please go through your company policies again and figure out whether it's illegal since you can lose you job!
Using Facebook proxies and other proxy websites could be illegal in office environments and you are liable to get caught and at least reprimanded.
My advice would be to lose the urge. Proxies are dangerous and if your work network gets infected you get fired and fined for the damages.
Best solution is to use your mobile phone to surf Facebook and Gmail instead of the computer. I am guessing though that you work in an environment where you are not allowed to take a cell phone to the floor.