Our server is set up to require authentication before sending email. Normally, it can authenticate you when you check your mail, so it allows you to send mail without any additional settings. However, sometimes when you send email without having checked your mail in a while, it will give you this message. Follow these instructions on how to set your mail program to authenticate:
Outlook Express or Entourage for Mac
Related Topics include: Hosting Frequently Asked Questions, TSP Email and Web Hosting, Spam Filtering.
