The computer failure affected the entire Royal Bank of Scotland (RBS) group, but Ulster Bank took longest to resolve the issue.

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The initial problem was due to a failed software upgrade within the Royal Bank of Scotland (RBS) group, which includes Ulster Bank and Nat West.

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Letters will be sent to customers of Ulster Bank, part of the RBS Group, from January that explains the change.

BBC: RBS and NatWest cut back on paper account statements

Ulster Bank customers in Northern Ireland were among the worst affected within the RBS group as it had the longest backlog of transactions to process.

BBC: Claims advice for Ulster Bank and RBS group customers

This money was invested in joint ventures with the Orana property group - most of the properties in these ventures have been effectively repossessed by Ulster Bank.

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