The variants of the message that you could see are: The remote computer requires Network Level Authentication, which your computer does not support. For assistance, contact your system administrator ...

Verizon is one of the many Internet Service Providers that require you to authenticate when sending mail. The purpose of SMTP authentication is to reduce email spamming and abusive mailing behaviors.

A password alone will not protect sensitive information from hackers--two-factor authentication is also necessary. Here's what security pros and users need to know about two-factor authentication.

Certificate-based authentication is a cryptographic technique that allows one computer to securely identify itself to another across a network connection, using a document called a public-key ...