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Unable to send emails after upgrading to Thunderbird 115 - empty pop-up window "Enter credentials for (xxx) on smtp.office365.com" - could not be sent because the connection to Outgoing server (SMTP) smtp.office365.com timed out.

  • 3 ŋuɖoɖowo
  • 7 masɔmasɔ sia le wosi
  • 5 views
  • Nuɖoɖo mlɔetɔ Toad-Hall

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All of a sudden, since yesterday, I cannot send any emails via TB since I upgraded to the 115-version. I've never experienced this before using TB.

Sending emails elsewhere from - by directly logging in to hotmail or from my phone - is no problem whatsoever.

But on TB115, when attempting to send a mail, an empty pop-up window appears with the headline "Enter credentials for (my emailaddress) on smtp.office365.com", before closing again. After a short while attempting to deliver the message, an error box reads: "Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) smtp.office365.com timed out. Try again."

SMTP settings: Outlook.com (Microsoft) smtp.office365.com Port 587 STARTTLS OAuth2

Any solutions?

All of a sudden, since yesterday, I cannot send any emails via TB since I upgraded to the 115-version. I've never experienced this before using TB. Sending emails elsewhere from - by directly logging in to hotmail or from my phone - is no problem whatsoever. But on TB115, when attempting to send a mail, an empty pop-up window appears with the headline "Enter credentials for (my emailaddress) on smtp.office365.com", before closing again. After a short while attempting to deliver the message, an error box reads: "Sending of the message failed. The message could not be sent because the connection to Outgoing server (SMTP) smtp.office365.com timed out. Try again." SMTP settings: Outlook.com (Microsoft) smtp.office365.com Port 587 STARTTLS OAuth2 Any solutions?

Wayne Mery trɔe

All Replies (3)

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SMTP settings: Outlook.com (Microsoft) outgoing smtp server: smtp.office365.com Port 587 Connection Secuiryt: STARTTLS Authentication Method: OAuth2

Is user name set up as full email address ? If no, then edit User Name.

Do you have any VPN operating - if yes, switch it off. Do you have anything currentlly using localhost eg: Apache ? If yes then switch it off until you have reset oauth.

Do you have cookies enabled ?

  • Settings > Privacy & Security

Web Content

  • select 'Accept cookies from sites'

Did you try a complete reset of password to get new oauth ?

  • Settings > Privacy & Security
  • Scroll to Passwords' section
  • clickon 'Saved Passwords'
  • click on 'Show Passwords'
  • Remove all outlook account stored passwords
  • if pop: mailbox://..account
  • if imap: imap://..account
  • smtp : smtp://..account
  • oauth://account...

Restart Thunderbird and it will force you to enter email address and password to allow Thunderbird access to server.

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@Toad-Hall Thanks for the reply.

I tried all of the above mentioned to begin with and nothing helped.

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UPDATE info:

There is a bug on sending issues with outlook and office365.

You are n ot the only person seeing this problem. I've asked people to test whether they get access using an app generated password and they posted info that they get access when using an app specific password. You would need to access Account Settings and change incoming server and smtp server settings as follows: Authentication Method: Normal Password

When asked for password, you would enter the app generated password and select checkbox for Thunderbird to remember it.

Some info at link on setting up 2FA and generating app specific password:

Please try this and report back on results. It may get you up and running whilst they work out whats going on.

  • Settings > Privacy & Security
  • Scroll to Passwords' section
  • clickon 'Saved Passwords'
  • click on 'Show Passwords'
  • Remove: oauth://outlook account...

If you see:

  • if pop: mailbox://..account
  • if imap: imap://..account
  • smtp : smtp://..account

Then right click on the relevant lines for incoming and outgoing and select 'Edit Password' Remove all content and then enter the 'app generated password'

click on 'Close'

If you did not see any mailbox:// or imap:// or smtp:// - do not worry, you will get a prompt.

Restart Thunderbird If prompted please enter the app generated specific password. Select checkbox to remember password and click on OK