An outage that affected Lloyds Banking Group customers was caused by the failure of two servers, the chief executive of TSB told the BBC.
The glitch affected customers attempting to make payments on their debit cards and when using cash machines on Sunday afternoon. Lloyds released a statement explaining the fault.
"Although the majority of transactions were unaffected, we are very sorry for the inconvenience that this will have caused," the statement said.
"At the same time, some customers encountered problems at approximately half of our 7,000 ATMs. This was resolved by 7.30pm, and all of our ATMs are now working.
TSB, Lloyds, Halifax and Bank of Scotland are all part of the Lloyds Banking Group, with 30 million customers in total.
TSB chief executive Paul Pester took to Twitter to apologise for the outage and to say it was caused by an HP server based in the UK. In reply to a tweet claiming foreign IT services' outsourcing was to blame for the problem, Pester wrote: "No truth in this. The issue was caused by a HP Server failing here in the UK."
@dangerfield_gem Gemma, no truth in this. The issue was caused by a HP Server failing here in the UK. PDP— Paul Pester | (@PaulPester) January 26, 2014
In further tweets, he added that 300 customers were in a queue to speak to the TSB call centre about the issues.
Card users often find themselves at the mercy of their bank's IT systems, with problems for RBS in 2013 and 2012 resulting in issues for hundreds of thousands of customers. In 2012, the problems were particularly severe, with customers experiencing issues for several days after the initial outage.
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