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Unable to send emails via Thunderbird

Thunderbird for Android Send and receive email
Platform34 replied
tomspitta
tomspitta

Hello, I’m having the following problem: When I try to add my Outlook email address to Thunderbird for Android, I get the error "Authentication unsuccessful: SmtpClientAuthentication is disabled for the Mailbox." This points to a help article that only describes a procedure using PowerShell—requiring domain admin privileges, which I don't have. Setting up the IMAP incoming server seems to work fine, but the outgoing server refuses to connect. This is just a personal account. The configuration is: Server: smtp.office365.com; Security: StartTLS; Port: 587; Authentication: OAuth 2.0; Username: mymail@outlook.de; Client certificate: None. I also tried the configuration using the server smtp-mail.outlook.com (with otherwise identical settings), but I get the same error. Does anyone have any advice?

Hello, I’m having the following problem: When I try to add my Outlook email address to Thunderbird for Android, I get the error "Authentication unsuccessful: SmtpClientAuthentication is disabled for the Mailbox." This points to a help article that only describes a procedure using PowerShell—requiring domain admin privileges, which I don't have. Setting up the IMAP incoming server seems to work fine, but the outgoing server refuses to connect. This is just a personal account. The configuration is: Server: smtp.office365.com; Security: StartTLS; Port: 587; Authentication: OAuth 2.0; Username: mymail@outlook.de; Client certificate: None. I also tried the configuration using the server smtp-mail.outlook.com (with otherwise identical settings), but I get the same error. Does anyone have any advice?

All Replies (1)

Platform34
Platform34
  • Top 25 Contributor

Hi @tomspitta

An issue report is open for this problem on github.

https://github.com/thunderbird/thunderbird-android/issues/10787

It seems to present itself with new outlook.com emails addresses, but not other microsoft accounts such as hotmail.

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