Nordea has asked some customers to refrain from making purchases while it tries to get to grips with a technical glitch that has disrupted its online banking systems for two days.
The unspecified problems first emerged on Tuesday, when customers found that their online accounts were either unavailable or showing apparently bogus transactions.
The bank on Thursday said that the "vast majority" of the issues had been fixed, including bill payments and card transactions, but that some customers may continue to experience difficulties.
Nordea has asked customers who are still struggling with card payments to contact a helpline for a one-on-one consultation.
"Corrective actions are still in progress and we will do our best to rectify the matter," says the bank in a statement. "To correct the problem, unfortunately, has taken a long time, which is obviously very disappointing from our customers' point of view."
In October, Nordea announced plans to take a EUR344 million impairment charge on its current IT systems and embark on a major project to rip and replace its core banking and payments platforms.
The Stockholm-based bank outlined its plans to boost IT spending by 30-35% over the next four-to-five years during its third quarter results presentation.