A Vodafone customer says he has lost weeks' worth of emails because of a failure in the company's system.
The telecommunications company cut its email platform at the end of November last year, but offered a forwarding service to customer's new accounts.
Some of the more more well-known addresses affected included ihug.co.nz, paradise.net.nz, vodafone.co.nz and clear.net.nz.
Many of the addresses were launched in the 1990s but the company said it was hard to tell how many customers were actively using their accounts.
Graeme Easte is one of those who had to change his providers and sign up for the forwarding service.
"They told me the forwarding system would work forever, so I didn't bother telling that many people that I had a new email address because of it.
"Then I realised that I still wasn't getting all of my emails, people would tell me that they had sent an important email but I never got it," Mr Easte said.
Mr Easte called Vodafone shortly before Christmas to tell them he was missing emails.
"I thought things had been resolved, but after numerous calls to them it wasn't until yesterday when someone told me the email forwarding service failed and that the emails have been lost."
Mr Easte believes he isn't the only person affected.
"Vodafone are saying the emails can't be recovered, they should send out the logs they keep so at least people can tell how many emails they have missed.
"They should also issue a statement saying that the forwarding system failed if that is the case for everyone, because some people have lost business through this glitch," Mr Easte said.
Vodafone said its specialist technology team is investigating Mr Easte's problem.
It said the majority of the 140,000 customers who had email services shut down had the auto-forwarding system work seamlessly.
"Vodafone is aware of an isolated number of customers who have experienced issues with auto-forwarding, in most cases, the customer has made an error in the auto-forwarding set up, which our specialist technology team has been able to easily diagnose and resolve.
"We urge any customer who is experiencing any kind of issue to please contact us and encourage all customers who have moved onto a new email platform to provide their new address to friends, family and businesses in the same way they would if their physical address changed," a company spokesperson said.