She called again, but Telecom staff were still unable to answer her questions.
"I understand that things happen sometimes with technology, but what I don't understand is why there has been absolutely no contact," she said. "I've had to do everything and no one has been able to tell me what is wrong."
Another upset client who also used her account for business said she had to direct clients to her mobile Vodafone Gmail account.
"To say this experience has been distressing is such an understatement," said the woman, who asked not to be named.
"It has happened at one of our busiest weeks, where a number of deadlines were due, and I have been left in the dark as to who has sent me what.
"What sort of surety or confidence can one have in Telecom. Their capacity is seriously in question."
She was told about 27,000 clients had business domain names and most were affected.
Telecom yesterday noted the problem on its website and said was working through a backlog.
The company said affected customers should now be able to send and receive email, but some might experience delays as backed up email traffic cleared.
It said it was doing all it could, including increasing capacity, to prevent it happening again.
Spokeswoman Jo Jalfon said while calls had been received by concerned customers unable to receive emails, "our call centres have been able to handle the volume".
She said the company would work to resolve the problem before it would consider options such as compensation.