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Can't Sent Emails with my Microsoft Account

  • 2 replies
  • 0 have this problem
  • Last reply by Dewi

Dewi
Dewi
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As of a month or so ago, I've been unable to send emails with my Microsoft account and have to click retry a bunch to get it to fetch my emails on startup.

I found this article and swapped the security for server settings and outgoing servers to SSS/TLS and the authentification method to 0Auth2 but now rather than asking for a password when I send an email, it's taking forever then failing, asking me to check my outbound settings. "Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again."

As of a month or so ago, I've been unable to send emails with my Microsoft account and have to click retry a bunch to get it to fetch my emails on startup. I found [[Microsoft OAuth Authentication and Thunderbird in 2024|this]] article and swapped the security for server settings and outgoing servers to SSS/TLS and the authentification method to 0Auth2 but now rather than asking for a password when I send an email, it's taking forever then failing, asking me to check my outbound settings. ''"Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again."''
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Chosen solution

The correct settings are: smtp.office365.com, 587, STARTTLS, OAuth2, email address. Still failing after restarting TB?

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sfhowes
sfhowes
  • Top 10 Contributor
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Chosen Solution

The correct settings are: smtp.office365.com, 587, STARTTLS, OAuth2, email address. Still failing after restarting TB?

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Dewi
Dewi Question owner
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Apologies for the late reply. Changing the settings to those you listed worked great, thanks!

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