Telkom Internet subscribers from the Johannesburg and Pretoria areas reported problems with their ADSL connections on 20 January 2016.
Subscribers reported outages in the region from 14:00, with reports of widespread outages surfacing from around 18:00.
Their lines synchronise and connect to the ISP, but users are unable to browse websites or use any online services.
Some subscribers reported being able to access Telkom Internet’s web portal at telkomsa.net, even though they weren’t able to browse other sites.
ADSL connections via different service providers were working.
While Telkom subscribers elsewhere in the country reported no loss of connectivity, one user in Bloemfontein said they were experiencing extremely slow browsing.
Telkom confirmed on Twitter that it was experiencing a network outage, stating that its technicians were attending to the problem.
Telkom said its points of presence in Johannesburg, Cape Town, and Durban were up.
However, some customers in the Northern Region of the country experienced intermittent or slow connectivity.
Engineers are working on identifying the problem and will resolve it as quickly as possible, said Telkom.