Glitch-plagued Mizuho Bank was unable to transfer customers' salaries into their accounts Friday because of a computer-system malfunction that is estimated to have blocked up to 620,000 transactions worth ¥125.6 billion since Tuesday, it said.
The number of unprocessed transactions over the past four days has climbed to 1.12 million, worth ¥775 billion, the key arm of Mizuho Financial Group Inc. said.
It remains uncertain whether the system will recover by the end of the upcoming three-day weekend, the bank said. Monday is a national holiday.
The trouble at one of Japan's biggest banks was apparently triggered by an overwhelming transaction volume at some branches. The computer problems will have a significant impact on the company unless its systems return to normal on March 25, which is pay day for many companies.
President Satoru Nishibori offered an apology at a news conference.
Most transactions, including remittances, at counters or automated teller machines at its head and branch offices, resumed Friday morning. But transactions conducted via convenience store ATMs remained suspended.
The malfunctions also caused over-the-counter remittances to come to a halt later in the day.
The bank will permit cash payments of up to ¥100,000 over the counter to customers inconvenienced by the delay in salary deposits, even over the coming weekend, although it plans to shut down all ATM services for the period, it said.
Financial services minister Shozaburo Jimi said at a news conference that the bank's persistent computer disorder "is extremely deplorable."
Asked whether the Financial Services Agency is considering disciplining the bank, a senior FSA official said, "We're not at a stage to consider it" yet.