
The Optus company sign is displayed in a store window in the central business district on Sept. 23, 2025 in Sydney, Australia. Lisa Maree Williams/Getty Images
The whereabouts of two emails related to the September Optus telephone outage that impacted emergency calls and led to three deaths dominated Senate Estimates on Oct. 8.
On Sept. 18, Optus conducted a network firewall upgrade that resulted in the emergency phone number 000 being inaccessible in parts of South Australia, Western Australia, and the Northern Territory.