SINGAPORE - The SingPass and CorpPass authentication systems are undergoing maintenance and will not be available to the public from Sunday (Feb 11) 10pm, to Monday 8am.

The "preventive maintenance" follows two outages on Thursday and Friday last week that hit users here trying to access hundreds of essential e-government services.

In a statement on Sunday night, the Government Technology Agency of Singapore (GovTech), the agency in charge of the maintenance of SingPass and CorpPass, said: "In order to prevent reoccurrence, we are embarking on a comprehensive system review."

This is in addition to the urgent preventive maintenance being conducted now.

Access to SingPass and CorpPass slowed to a crawl for about four hours on Friday after a six-hour outage on Thursday.

The outages disrupted hundreds of essential e-government services such as the filing of employees' Central Provident Fund (CPF) contributions and work permit applications.

"Both incidents were not cybersecurity-related, and occurred due to a server fault. We have investigated and since replaced some server hardware," GovTech said on Sunday night.

The incidents prompted some IT professionals to express concerns about the robustness of the gateway systems and the impact on the new national digital identity (NDI) system.

The NDI phone app is layered on SingPass. When introduced, it will give Singapore citizens a unique digital identity and authentication to perform secure paperless transactions.

Set up in 2003 for Singapore residents to access e-government services, SingPass has more than 3.3 million registered users and supports 57 million e-government transactions, including the filing of income taxes, parking fine payments and foreign domestic worker applications.

CorpPass, rolled out in September 2016, is meant for corporate transactions, including the filing of corporate taxes and work permit applications.