The Royal Bank of Scotland (RBS) and NatWest have suffered from yet another IT glitch resulting in thousands of customers unable to access their accounts in the UK.
RBS, which owns NatWest, had to provision £125m for costs arising from an outage in June 2012, and will risk further costs from its latest systems failure as customers vent their frustration and ask for compensation on social media site Twitter.
The outage came on what is thought to be one of the busiest shopping days of the year, Cyber Monday, and began at about 6:30pm, with customers complaining that they were not able to pay for shopping or petrol using their bank cards.
The banks' smartphone apps on Android and iOS, and the online banking websites, were also affected.
RBS and NatWest's Twitter accounts, which were flooded with tweets from disgruntled customers, said: "We're aware of some technical issues and are working hard to fix them. Sorry and thanks for your patience."
It later added that "if customers have been left out of pocket as a result of these problems, we will put this right".
On its system status page, RBS claims that the issues that affected its customers last night have now been resolved and all of its services are now working normally.
In March this year, RBS had a hardware fault that affected its online banking services and bank cards.
It is so far unknown what caused the latest outage, but it will come as a major blow to the firm, particularly as group chief executive Stephen Hester had said that the June 2012 incident had left a "significant blot" on RBS's reputation.
In August last year, Hester said that the bank was working to ensure that these types of issues do not re-occur.
"While we have significantly increased technology spend over the past three years, there is clearly more we need to do to ensure reliability for our customers," he said.
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