Attendees demanded refunds and threatened legal action after complaining of awful food, enormous lines for toilets and ordinary music at NYE Above the Harbour.
"The organisers and caterers, in good faith, are currently processing any complaints and a formal process is in place to address and resolve these issues," event organisers said in a statement on Sunday.
Revellers swamped social media to slam the "complete joke" of an event.
Many attendees, including Chris Lee, were highly critical of its culinary offerings.
"I cannot believe you charged us over $400 for an `all inclusive' event with only three food stalls for thousands of people," he posted on Facebook.
"We had to wait 2.5 hours to get fed some disgusting dried up pork buns that tasted like cardboard."
Angela Micallef, from the United Kingdom, said ticketholders were robbed.
"I spent most of my night queuing up for one thing or another and didn't get to spend time with my family," she said on the event's Facebook page.
"The beer tent ran out of cider early on, the music/sound quality was awful and the kids' corner comprised an air hockey table."
Organisers said on Sunday that they felt for aggrieved attendees and would deal with complaints on a case-by-case basis.
"The organisers and caterers empathise with patrons and are themselves disappointed with the issues that have arisen," they said.
"They have poured significant time, resources and personal effort into the event's planning, and are personally affected by the unfavourable outcome of their efforts."