A large group of O2's mobile customers are still experiencing the after-effects of a 12-hour outage, which brought mobile services including data, SMS and calls to a halt.
The problems began yesterday at 10.45am, according to O2's network status reports. They were fixed at a quarter to midnight, meaning many users woke this morning to find undelivered texts and missed calls from Thursday.
Not happy @o2 - Yesterday I could send SMS but not receive; At 08:48 today, 9 SMS from yesterday arrived, a couple "were" worth money to me!— Alan Glenister (@ukahg) October 4, 2013
However, some users are reporting that they are still suffering problems, indicating that there could be further problems to come.
The network said the outage was "the result of unexpected congestion caused during routine upgrade work on our 2G and 3G networks".
The problems affected one percent of O2's customer base, the network said, but with 22.9 million mobile users, that still equates to around 229,000 customers. The outage is certainly poor timing for the network, which is in the process of trying to lure consumers towards its newly launched 4G offering.
On Tuesday, O2 released an update for users of the iPhone 5S and 5C that allowed customers to access its high-speed 4G network, which was not available when Apple's two latest devices launched.
Earlier this week, rival 4G network EE also suffered an outage that affected customers across the UK. The firm asked users to turn their devices off and on again.
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