Datalex now expects to record a loss of between $4m and $6m for 2018, considerably higher than its previous forecast.
The travel software company had previously forecast a loss of $1m to $4m, but said further progress on an audit of its accounts had led it to increase that figure.
Datalex undertook an audit in its 2018 accounts after a review discovered "significant accounting irregularities" at the firm.
The PWC report said the company's figures for the first six months of 2018 were "materially overstated", with some revenue recorded before it had actually been received.
A delay to Datalex's publication of full year results led to the suspension of its Dublin-listed shares in April, while chairman Paschal Taggart and CEO Aidan Brogan also resigned.
Earlier this year the firm agreed to a €6m loan from the investment vehicle of Dermot Desmond, who also increased his stake in Datalex to 29.9%.
In a stock market announcement this morning Datalex said acting CEO Sean Corkery and recently appointed CFO Niall O'Sullivan "have been leading a comprehensive review of the Datalex business".
It said shareholders would be updated on the result of this review - as well as the firm's outlook for 2019 and 2020 - would be given at its AGM, which is currently due to take place on 17 September.
It said it expected to publish its annual results for 2018 ahead of that meeting.
Datalex provides ecommerce software to the travel industry, specifically airlines. Clients include Lufthansa, Aer Lingus and Jet Blue.