He said that the problem had arisen when; 'A file due to be processed overnight wasn't.'
A statement issued this afternoon by the bank noted that; 'As of noon (Sydney) the Commonwealth Bank finalised the processing of a late running file. '
The bank claimed that the file primarily related to business customer accounts, but that a small number of retail customers had also been affected.
Processing the rogue file during the day forced the bank to temporarily suspend access to CommBiz and NetBank. Its statement claimed that; 'The file has now completed processing, all accounts are now up to date and there is no impact to our online channels. '
The bank also acknowledged that; 'Customers whose accounts required data from the late running file may have had difficulty accessing cash though ATMs during processing this morning. As the file has now been processed, this is no longer an issue for those customers. '
The NAB still has a notice on its web site stating that while the majority of customer payments and transactions have been completed, and most account balances are up to date; 'We know that some customers are still experiencing inconsistencies and we're actively working to address these as soon as possible.'
That the CBA, arguably the furthest along the transition to a modern core banking system, can still fall victim to the failure of a batch process, demonstrates that the promise of failsafe bank computing is still a way off.
And with a raft of changes possible as a result of Wayne Swan's banking review, coupled with the requirement for banks to overhaul their systems to ensure compliance with Basel III over the coming years, banks' IT challenges will only increase.