Telecom is putting the pressure on Yahoo to front up over a security breach that resulted in a mass of spam emails.
A review over the next two months will investigate a series of issues that Telecom said has affected the email service badly and led to repeated apologies to its customers.
Telecom retail CEO Chris Quin said saying 'sorry' to its frustrated customers was no longer good enough.
The review was triggered after hundreds of thousands of emails were sent out from Yahoo!Xtra users accounts to anyone in their contacts list.
The email consisted of a generic greeting and a link to a website asking for personal details including credit card numbers.
Telecom outsourced its Xtra email service to Yahoo in 2007.
"It was the right thing to do at the time in terms of meeting our customers' desire for an ongoing email service associated with their Telecom broadband account," Quin said.
"However, the global email environment has changed markedly since then and we believe the time is right for a comprehensive review of our approach in this area."
- The Dominion Post