Up to 5000 bank clients of National Australia Bank (NAB) flooded its official website to file damage claims arising from NAB's computer system glitch that started on Wednesday morning last week and extended onto the early part of the current week.

The problem stemmed from the erratic software that suddenly stopped its overnight data processing functions and consequently resulted into the non-payments of customer accounts the next day, also botching NAB's ATM transactions as the bank's frantic response to check the issue failed to arrest the system meltdown.

NAB finally corrected the issue on Tuesday but not before its millions of customers were prevented from accessing their accounts and employees went unpaid over the weekend while benefit providers charged fees for late payments caused by the system glitch.

NAB enjoined its customers to fill up the online form on its website for their damage claims, which the bank said should settle repayments for any third party costs incurred from utility providers, lenders and other services due to the technical problem that either rendered clients unable to transact through their accounts or found their savings emptied.

NAB said that as the system is being restored, all the issues encountered during the whole span of the meltdown have been corrected or now in the process of resolving as the bank assured clients on its website that "we will proactively undertake this work over the coming weeks, without the need for customers to contact or notify us."

While generally the problems have all been dealt with, NAB has admitted that a number of clients were still unable to access their accounts but these are isolated cases as the bank provided confirmations that "the majority of customer payments and transactions have been completed and account balances are up-to-date."

The bank also advised its customers that they may still encounter inconsistencies on their banking transactions but it stressed that NAB is continuously "working to address this issue as soon as possible, and there is no action that customers need to take."