The Airport's Sally Fielke says the issue has been fixed by airport technicians and the software provider.
Worldwide and domestic flights were both affected by the fault in terminals one and two, with passengers and staff alike not able to pass security.
Qantas' domestic Terminal 3 has not been affected.
Jetstar expects all their flights will be back on schedule by midday, after its morning flights were delayed by an hour on average.
Why CFIUS Is Intervening in Broadcom's Qualcomm Bid
Broadcom said it is run by a board of directors and senior management team consisting nearly entirely of Americans. Qualcomm still is awaiting approval from regulators in China to acquire NXP.
"We're working to resolve the issue as quickly as possible and thank you for your patience".
Passengers are seen waiting in line due to hardware and technical issues at the Domestic Airport in Sydney, March 9, 2018.
"Virgin Australia is holding flights to minimise any disruption to passengers and working to reaccommodate any affected passenger".
"We're advising passengers and visitors to avoid T1 and T2 until further notice".
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FOX's " Red Sparrow " didn't beat Black Panther , but the film did land in second-place after a $17M debut across 3,056 locations. With how it's holding, Black Panther should become just the seventh film in history to break $600 million at the US box office .
"There may be some delays as a result, however guests are advised to arrive at the airport as planned for their upcoming Virgin Australia flight", it posted on Twitter.
All planes yet to take off were instructed to disembark so passengers could be re-screened.
Security screening was closed for 30 minutes at the airport as federal police investigated the matter.
It affected systems including the airport's CCTV, meaning passengers could not be screened for about two hours.
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ICICI Bank is the leader of a consortium of lenders to Mehul Choksi's Gitanjali Gems , and has an exposure of ₹500 crore. Kochhar and Sharma will appear before the (SFIO) in Mumbai on Tuesday afternoon, sources in the agency said.