"As a result of this, we are intending to move the market straight into a pre-close status.
However, not long after that the company said it would not be be transitioning to a pre-close status at 4.45pm.
"Participants remain disconnected. The market remains in the current status. NZX has determined not to re-open the cash markets today. This includes not running a closing auction.
"We will continue to work towards restoring connectivity to the NZX Derivatives Market."
The outage comes as the company reporting season draws near.
In April NZX beefed up its new technology sub-committee with the appointment of computer expert Peter Jessup as an independent member.
The move is one of a series of steps being taken by the local exchange as it followed the recommendations of a scathing Financial Markets Authority report issued after the cyber attacks it suffered in August and September, plus technical issues earlier in the year.
The market watchdog, which found a pattern of under-resourcing and under-investment, also said the NZX's next steps needed to include hiring a relationships manager, a chief risk officer, a head of network architecture and a head of IT security.