The company said Wednesday afternoon the system would be fixed in four phases.
Customers can review their accounts on a new user interface, but the live price board has yet to reappear.
Trading will resume in the second phase, but the company has not said when. It said it is reestablishing connections with the Ho Chi Minh Stock Exchange and the Hanoi Stock Exchange, which cut them off on Monday.
This means customers have been out of the market for three days and are heading into a fourth.
VNDirect, which was attacked by an international group of hackers on Sunday, has assured that clients’ information and assets are safe and not affected.
It had 7% of all investors’ accounts on the Ho Chi Minh Stock Exchange as of last year, the third highest after SSI Securities Corporation and VPS Securities.