if you are seeing errors when trying to send or receive emails you may be seeing this becuase you have an Xtra / Yahoo email account.
Starting from around Sunday some Yahoo email accounts were compromised and a spam attacked launched.
If you have an xtra.co.nz and your email program has started asking you for a password you will need to contact Xtra on 0800 22 55 98 to have your password reset.
See this article on the New Zealand Herald's website:
http://www.nzherald.co.nz/technology/news/article.cfm?c_id=5&objectid=11165400