A corrupted file has been blamed for one of the largest financial institutions in Australia suffering a systems meltdown that saw thousands of customers out of cash over the weekend.
The corrupt file on the mainframe has been cited as the cause of the system failure in National Bank of Australia (NAB) and Channel Register says a failed upgrade last Wednesday caused the original corruption.
The effect the corrupted file had was chaotic and led to private and business customers failing to access their accounts at ATM machines.
The file corruption also caused payments to stop or to be read incorrectly, incorrectly debiting certain accounts, adding illusory debts to other accounts, conducting money transfers to other banks, as well as other NAB customers.
NAB has since run full-page adverts in Australian papers to express its regret for what happened and promised to fix the issue.
NAB operates 1,714 branches and service centres and has 2,939 ATMs globally.