A mystery technical glitch has effectively shut down the ASX, with trading abandoned at 3pm Monday.
Trading was halted about 10.30am AEDT due to "market data issues".
The underlying issue has been identified and trading should recommence at 10am on Tuesday.
"A resolution path is in place is in place to allow trading to commence tomorrow at 10am," the ASX said in a statement.
"In the bigger picture, it's mostly just a nuisance," IG market analyst Kyle Rodda said.
"But there'd be traders out there with open positions who might be very worried about where there trade might end up when the exchange finally reopens," he told news.com.au.
"There's just a degree of frustration out there today.
"Things will open back up eventually and things will fall wherever they may.
"However, it was looking like a really positive day, so there's a degree of disappointment that many investors may have missed on the opportunity to take advantage of the rally."
"ASX apologises for the disruption and is working to rectify the issue as soon as possible," it said in a tweet.
The ASX said it is continuing to investigate the issue causing today's market outage which halted about 10.30am AEDT.
The unusual situation has sparked a flurry of activity on social media.
In a tweet from CommSec explaining that the ASX was down, one user commented "WTF!" while another user simply said "Oh boy".
Investor Scott Phillips commented: "It'll open again at some point. We can trade then. In the meantime, enjoy the peace."
Some left some laughing emojis while others left comments with some unsolicited advice: "Have you tried to switch it off and on again??"
Another commented: "Take the cartridge out of the Super Nintendo and blow on the inside gently, that should fix it."
Some Twitter users were concerned about a "cyber attack" or if the securities exchange got "hacked".
Another Twitter user commented: "Every man and his dog must've decided to jump back on the market today now that the US election is old news. Was having a splendid morning – all my shares in the green for today – till it decided to sh*t itself."
Another said: "I want the glitch that turns my losses into gains please."
The market opened in the green on Monday morning, with the ASX 200 rising about 1.3 per cent to 6484 at around the time it halted.
This isn't the first time the ASX has experienced glitches.
The ASX's trading systems triggered a delayed market open and an early closure in September 2016 due to a hardware failure, according to Bloomburg.
In October 2011, trading was halted for almost four hours by a technical disruption just before the open.