on 12-04-2012 13:12
Check you have APN settings in your phone setup.
Go into settings - Networks - Mobile networks - Access point names.
you should have 'o2 mobile web' selected. If not this needs to be setup.
or you might not be connected to the network yet if you're a new customer.
Not sure what the APN settings are now because i'm on the Galaxy Nexus and its slightly different to my old G2 in settings. A google search will find then no probs though if you need them.