A Barclays computer glitch left the bank's customers without the use of its ATM machines and online banking for much of the Easter bank holiday weekend. Services were still in the process of returning to normal during the day on Tuesday, according to some customers.
The problem struck at 0100 (BST) on Sunday, around the time the clocks went forward, leading many to believe the computer glitch, to which the problems were attributed, was related to a problem with the clock settings.
However, Barclays today told ZDNet UK sister site silicon.com that earlier media reports suggesting the change to British Summer Time was responsible were wide of the mark.
A spokeswoman for the bank also dismissed suggestions that the culprit had been a manager who set the clocks back rather than forward.
"It was an issue with a small piece of our IT hardware," said the spokeswoman. She added the bank is currently investigating exactly what went wrong with the kit, which was not named.
Around 1,500 cash machines in the south of England went offline and stayed offline until around 1700 on Sunday evening.
Some customers are calling for compensation and the bank says it will listen to all complaints.
"We're asking any customers who experience any financial loss as a result of this problem to contact us and we will address them on a case-by-case basis," said the spokeswoman.