I don't know whether it applies to your situation, but it's quite common for people within an organization not to be able to access their own public web sites.
The problem is usually that the server holding the public web site lives outside the security zone that protects the network's computers from external hackers, and for some reason that makes the server inaccessible to computers on the local network. If you explain the problem to a network person (if you have one) I'm sure they'll be able to fix it.
'I can't even fit all my wife's clothes into a suitcase for travelling. So you want me to believe we're going to put all of the planets and stars and everything into a sandwich bag?' - q3psycho on the Big Bang