The O2 network has seen a serious outage prevent its users from making calls and accessing 3G calling, web and messaging services since roughly 1pm on Wednesday afternoon (11/07/2012).
O2 have now fixed issues relating to their 2G signal problems, but 3G service remains patchy at best.
A spokesman for O2 said: "Our 3G service is starting to restore and customers should expect to see a gradual return of data services as the day progresses.
"Customers affected may wish to try switching their mobile phones off and on as service returns.
"We are sorry again for the inconvenience this has caused some customers and can provide reassurance that we continue to deploy all possible resources, and will do so until full service is restored."
Some 23 million users are still thought to be affected by the outage, and for many we'd expect advice to "switch their mobile phones off and on again" will not be enough to stunt their anger.
Have you been affected by the O2 outage? Has it caused major problems, or just stopped you checking out LolCatz videos on YouTube? Share your stories in the comments section below!