Ulster Bank has been hit with a three and a half million euro fine over its 20-12 IT meltdown.
The fine is the largest paid over to the Central Bank.
More than 600 thousand Ulster Bank customers were unable to access their accounts and payments weren't processed over a 28 day period in 2012.
The Central Bank said the IT failure caused significant and unacceptable inconvenience to customers.
Ulster Bank said in a statement that it accepts the findings and that it has invested in technology to prevent future glitches.
The bank has paid out almost 60 million euro in compensation to customers.
