A hardware failure in a Scottish RBS Group technology centre caused a NatWest bank outage, according to a source close to RBS.
The outage, which started mid-afternoon on Thursday, continued until the middle of the evening. It prevented customers from using online banking services or doing debit card transactions. However, some people were still experiencing residual effects on Friday morning, the source said.
The majority of customers affected were with NatWest, ZDNet understands. RBS is also the parent company of Ulster Bank, Coutts and other financial institutions.
The fault occurred in an Edinburgh technical centre, and was not linked to a batch-processing fault that caused widespread disruption last month, the source added.