Incoming or outgoing or both ? Pop or imap ?

If pop are you using these settings ?

Are you using these settings?

Incoming POP server: pop.earthlink.net Port: 995 Connection Security: SSL/TLS Authentication Method: Normal Password User name: email address

outgoing server (SMTP): smtpauth.earthlink.net Port: 587 Connection Security: STARTTLS Authentication Method: Normal Password User name: email address

If you make any changes then restart Thunderbird.

If you have just updated Thunderbird then it is possible your Firewall may need to have Thunderbird reset to be allowed. What Anti-Virus Firewall are you using ?

Thank you for your response. Sorry for my delayed response but have spent much time between earthlink and my password manager, lastpass, to resolve the problem. Earthlink does not support connection security except when using earthlink webmail. However, when my earthlink account stop being accepted by thunderbird my previous settings of connection security/none and authentication method/encrypted password were no longer accepted. I suspect it was a password issue. After resetting my password and being certain the same word was being tracked by lastpass I finally got the email accepted by thunderbird using my old connection security and authentication method settings. Again, thank you for your response. P.S. I use PC Matic. William