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can not send email from thunderbird with Office 365

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  • Last reply by Stans

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Sending of the message failed. Unable to authenticate to Outgoing server (SMTP) smtp.office365.com. Please check the password and verify the 'Authentication method' in 'Account Settings | Outgoing server (SMTP)'

thunderbird is 102.7.1

set up is as directed from thunderbird server Name smtp.office365.com port 587 username is correct authentication method OAuth2 connection sevurity STARTTLS

times out everytime!

Sending of the message failed. Unable to authenticate to Outgoing server (SMTP) smtp.office365.com. Please check the password and verify the 'Authentication method' in 'Account Settings | Outgoing server (SMTP)' thunderbird is 102.7.1 set up is as directed from thunderbird server Name smtp.office365.com port 587 username is correct authentication method OAuth2 connection sevurity STARTTLS times out everytime!

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Are you using Office 365 email with a private (custom) domain, or are you using a shared public domain such us "outlook.com", "hotmail.com"?. This is the part of your email address that comes after the @ character. Office 365 still doesn't work with OAuth2 when using a public shared domain (MS refers to these as "personal" accounts), at least on my end using Thunderbird 102.7.1. What works for me, is to use Normal Password authentication (which is what Thunderbird defaults to anyway), and an app password generated via my Microsoft Account's Security settings page. See https://support.microsoft.com/en-us/account-billing/using-app-passwords-with-apps-that-don-t-support-two-step-verification-5896ed9b-4263-e681-128a-a6f2979a7944