KEY POINTS:
A huge spam assault on Xtra's email network is to blame for emails taking days to be delivered, says Telecom.
Several customers have vented their frustrations on an Xtra website message board saying some emails were days late.
The problems appear to be a continuation of the problems that plagued the network a few weeks ago.
One woman on the Xtra message board said she had forwarded emails from a computer 10m away from her own and sometimes had to wait up to three days to receive them.
Another woman contacted the Herald and said she tried to email another Xtra customer several times after completing a Trade Me auction, only to find out the other person had not received her emails.
General manager of consumer marketing, Kevin Bowler, said spammers intentionally targeted Xtra "with a flurry of false connections which are making it difficult for some mail servers to instantly connect to Xtra".
He said the record volumes of spam meant such problems would be "an unfortunate and on-going reality of the internet not specific to any provider".
Telecom filtered a record 226 million items of spam in September, compared with 65 million for the same time in 2005.
Mr Bowler said Telecom had invested "tens of millions of dollars"in email and anti-spam software and worked closely with two of the world's leading anti-spam vendors.
"Spam and email security are areas that we have been placing significant resource and focus on."
But at least one Xtra customer is not convinced and believes the problems are due to Telecom's underinvestment in technology.
"I think it's too much of a convenient excuse," said Kevin Wright. In recent weeks he had waited "up to 2 1/2 days" to receive emails from the US.
"It appears like they have had some new spam filters put in which is slowing down traffic from offshore. Ten to 30 minutes is okay but 2 1/2 days is completely unacceptable."