A FOUR-DAY email outage for Telstra customers has finally ended after Bigpond fixed its server problems.

Telstra spokesman Martin Barr said the problem with email login access and delays since Monday was now rectified.

"We have updated the service page and the issue is resolved," he said.

Mr Barr could not confirm how many customers had email delays or accounts quarantined.

"Those accounts have been progressively unlocked," he said.

"Up until today there was a very small amount left (two dozen)."

This week the Telstra website told customers: "Some customers may experience issues accessing their accounts.

"Technicians are treating this issue as a priority and are working on the problem. We apologise for any inconvenience this may cause you."

The email blackout affected Telstra dial-up, cable, ADSL, satellite and Next G wireless internet accounts Australia-wide.