National Australia Bank (NAB) spokesman George Wright would not provide technical description of bank's computer difficulties in AUSTRALIANIT article. Wright denied rumors of a botched mainframe upgrade, hackers or virus as reason for glitch. NAB does batch processing for other banks and delivers files daily. "On early Thursday morning, IT departments at financial institutions such as Commonwealth Bank, Westpac, ANZ, HSBC, Citibank and Bank of Queensland went on high alert when they did not receive the files." It's one of Australia's biggest banking bungles. NAB is placing blame on human error as "...someone from NAB's IT department who had access to the system inadvertently uploaded a file that 'corrupted' the system." Many NAB bank customers were caught without cash as salaries did not make it into their bank accounts.