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The login attempt to the server smtp.office365.com with the username XXXX has failed.

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  • Last reply by david

Hello:

I use Thunderbird for work. I have several email accounts configured in it, including Gmail, my company's email, and Outlook. I recently added a new Outlook account, and I haven't been able to send a single message. The error I'm receiving is the one described in the title. It's worth noting that I have another Outlook account working perfectly. I've tried every solution I've found online, and none of them have worked, including enabling SMTP in the account settings, making sure OAUTH is enabled, using smtp.outlook.com or smtp.office365.com instead of smtp.mail.outlook.com, enabling two-factor authentication, changing my password multiple times, etc.

Hello: I use Thunderbird for work. I have several email accounts configured in it, including Gmail, my company's email, and Outlook. I recently added a new Outlook account, and I haven't been able to send a single message. The error I'm receiving is the one described in the title. It's worth noting that I have another Outlook account working perfectly. I've tried every solution I've found online, and none of them have worked, including enabling SMTP in the account settings, making sure OAUTH is enabled, using smtp.outlook.com or smtp.office365.com instead of smtp.mail.outlook.com, enabling two-factor authentication, changing my password multiple times, etc.
Attached screenshots

All Replies (3)

Try this: - click 'account settings' - highlight account in left side bar - now, in lower right, click the 'edit SMTP server' button - does the next screen show the email address of this new account? Or does it show the email address of a different account?

If i shows a different email address, you're using the wrong SMTP server. back up to prior screen, click the dropdown menu for 'Outgoing SMTP server' and select the one for your account.

Hi David, thank you for your response. I see the same email as the account, so I assume that's fine. I attached a photo so maybe you can identify an error.

I cannot speak for MS. My personal Outlook account, which works fine, uses smtp.office365.com

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