This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Este fío arquivouse. Faga unha nova pregunta se precisa axuda.

Error sending mails following update to 78.4.0.

  • 1 resposta
  • 1 has this problem
  • 1 view
  • Last reply by Mark-E-H

Mark-E-H
Mark-E-H
more options

This morning Thunderbird was updated to 78.4.0. Incoming mails (POP3) work fine. But suddenly outgoing mails are rejected: "An error occurred while sending mail. The mail server responded 450 4.1.8 <my email>: Sender address rejected: Domain not found. Please check the message recipient ".... recipient ..." and try again.

Sending mails worked fine till update was installed, and I have not changed any SMTP settings. Same error for all recipients of mail.

Any suggestions?

This morning Thunderbird was updated to 78.4.0. Incoming mails (POP3) work fine. But suddenly outgoing mails are rejected: "An error occurred while sending mail. The mail server responded 450 4.1.8 <my email>: Sender address rejected: Domain not found. Please check the message recipient ".... recipient ..." and try again. Sending mails worked fine till update was installed, and I have not changed any SMTP settings. Same error for all recipients of mail. Any suggestions?

Chosen solution

Turned out to be a problem with the provider. Problem is solved.

Ler a resposta no contexto 👍 0

All Replies (1)

Mark-E-H
Mark-E-H Question owner
more options

Chosen Solution

Turned out to be a problem with the provider. Problem is solved.