Scheduled maintenance by Australia Post's IT team brought down several of the organisation's systems on Monday, as first reported by the ABC.
An Australia Post spokesperson told ZDNet that while outages do not occur frequently -- there have been none in the last two years -- the technical issues have affected some of its online services, electronic payments, real-time parcel tracking, and internal emails.
However, Australia Post reassured that mail and parcel delivery have not been affected.
The spokesperson added that IT has made "good progress" on amending the issue.
Australia Post has been under continued pressure to focus on providing e-commerce-driven logistics and delivery solutions to cope with the decrease in traditional letter deliveries.
During the 2013-14 financial year, the government-owned organisation reported that profit after tax was down 34.5 percent to AU$116.2 million from the previous year.
A large part of the decline was due to its mail business seeing a significant drop in letter volumes -- of which 97 percent was the result of large corporations and government departments moving mail services online -- and continued high fixed costs.
Australia Post has been signing on additional Australian businesses to its MyPost Digital MailBox since it launched in 2012. There are now 46 Australian businesses and government-owned organisations already using the service, including Westpac, Telstra, AMP, Sydney Water, and the federal government's MyGov.