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.

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

Lolu chungechunge lwabekwa kunqolobane. Uyacelwa ubuze umbuzo omusha uma udinga usizo.

SMTP server suddenly unreachable

  • 1 baphendule
  • 2 zinale nkinga
  • 7 views
  • Igcine ukuphendulwa ngu Matt

more options

For a few year thunderbird works fine. Since today I can't send any mail. I got the following message:

ErrorMessage: Sending of the message failed. The message could not be sent using Outgoing server (SMTP) securesmtp.t-online.de for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again..

I check the settings, all fine. I test the settings with Outlook and it works. I use Thunderbird 38.6.0 unter Windows 10 on two computers. Since today both have the same problem.

SMTP-Server: securesmpt.t-online.de; Port 465 with SSL/TLS

receiving mails works fine.
For a few year thunderbird works fine. Since today I can't send any mail. I got the following message: ErrorMessage: Sending of the message failed. The message could not be sent using Outgoing server (SMTP) securesmtp.t-online.de for an unknown reason. Please verify that your Outgoing server (SMTP) settings are correct and try again.. I check the settings, all fine. I test the settings with Outlook and it works. I use Thunderbird 38.6.0 unter Windows 10 on two computers. Since today both have the same problem. SMTP-Server: securesmpt.t-online.de; Port 465 with SSL/TLS receiving mails works fine.

All Replies (1)

more options

Have you contacted your provider to see if they have an issue today?