The Australian Taxation Office (ATO) has headed back to a period of time it would likely rather forget, reporting on Tuesday morning its online services were unavailable.
"Our online services are currently unavailable. We're working on a fix as a priority & will provide an update when the issue is resolved. Apologies for the inconvenience," the ATO posted in a tweet.
At 1.14pm AEST, the ATO updated Twitter, saying it was still working on a fix.
"Thanks for your patience while we continue work to restore our online services. Our technicians are still busy working on a fix. We're sorry for the inconvenience & will provide another update as soon as we can," it added.
The outage comes after the ATO spent a good 12 months dealing with IT issues that started in late 2016 including "one-of-a-kind" SAN outages.
Although the ATO said issues were rectified, further service disruptions ensued.
The government department had to turn its mainframe off and switch it back on again in July 2017 when a disruption occurred five days into the new financial year.
Its last outage was in March last year, after scheduled maintenance ran overtime.
After it was revealed in July that the ATO had prevented users from accessing its website if certain adblockers, firewalls, and anti-virus software was in place, the government entity removed a "bug" it said was present on its ato.gov.au page.
At the time, an ATO representative said its site-trackers collected anonymous usage data, and that it was working on allowing these to be disabled via browser add-on/adblockers.
The ATO told ZDNet that it has identified the issue and is working to restore services.
It also said that Tuesday's issue is unrelated to previous incidents.
Updated at 4.20pm AEST, 4 June 2019 : Added comments from the ATO.
The department did not alert users that planned maintenance would take its websites offline.
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