Three days after millions of Australians headed to bed frustrated and angry, having unsuccessfully tried to complete the census online, we still don't know exactly what went wrong, or who to blame.
Politicians have chosen to blame the only non-government entity involved - US-based tech giant IBM, which won the $9.6 million contract in 2014 to design, develop and implement the online census.
Who's responsible for the census hack?
There are a few different theories as to who is behind the disruption on census night. Fairfax David Wroe explains the possibilities.
"The denial of service attacks were completely predictable and should have been repelled readily. They weren't because of failures in the system that had been put in place for ABS by IBM, and as I said there are issues for both IBM and ABS about that," Prime Minister Malcolm Turnbull told radio station 2GB on Thursday.
"There is no doubt that there were serious failures in the systems preparation for an entirely predictable denial of service attack."
Meanwhile Senator Nick Xenophon has said taxpayers should ask IBM for their money back.
Even Treasurer Scott Morrison has raised the possibility of legal action.
"If there are issues relating to the service provider in this case, then you could expect us to pursue that to the nth degree," Mr Morrison told ABC radio on Friday morning.
Last night an IBM spokeswoman finally came out publicly to say the Australian Signals Directorate [ASD] confirmed no data was compromised and it "regret[s] the inconvenience that has occurred".