It now predicts a net loss of 995bn yen (Â£7bn) for the year to March, up from its earlier estimate of 950bn yen.
The firm was demoted to the second tier of the Tokyo Exchange after confirming its liabilities outweighed its assets.
It also got regulatory approval to delay filing its annual earnings again, this time until 10 August, after a previous deadline extension to 30 June.
Failure to gain an extension would have put the troubled company's stock exchange listing in further jeopardy.
In April, Toshiba said its future may be in doubt after facing a series of difficulties.
An accounting scandal that was uncovered in 2015 led to the resignation of the chief executive and several senior managers. The company was found to have inflated the previous seven years' profits by $1.2bn.
The firm was dealt another blow in January when it became clear its US nuclear unit, Westinghouse, was in financial trouble.
Toshibas's dire financial position has forced it to try to sell off its highly prized chip unit.
The company has named a consortium of Bain Capital and Japanese government investors as the preferred bidder for the business
But US-based Western Digital, which jointly runs Toshiba's main chip operations in Japan, has filed a request with the International Court of Arbitration to stop the sale going ahead.
On Friday Toshiba chief executive Satoshi Tsunakawa said his firm was willing to talk.
"Western Digital used to be a good partner, so we want to continue talks. I'm disappointed with the current dispute," he said.
"We want Western Digital to jointly invest to fight against Samsung. It will be so disappointing if we can't do so because of the dispute."
He said Western Digital's offer had not been at the right price and that the US firm had wanted to take control of the unit, rather than keeping Toshiba executives in charge.
Toshiba is the world's second-largest chip manufacturer. Its products are used in data centres and consumer goods worldwide, including iPhones and iPads.
Ailing electronics giant Toshiba has said its losses for 2016 may be greater than it had previously forecast.