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All of a sudden, SMTP authentication failure to (all my) Outlook accounts

Thunderbird Send and receive email
samopn
samopn

As the title says, over the last two days Thunderbird won't do SMTP authentication to Outlook. It has worked happily for years and nothing at my end has changed.

I've the latest version of Thunderbird - 140.15.0esr (64-bit) - and this is Windows 11. It works happily from the Outlook desktop so the password is correct.

The authentication method is OAth2 and connection security is STARTTLS. Server is smtp.office365.com and port 587.

Anyone else having issues? Presumably MS have changed something (again)

Has anyone any suggestions on how to resolve?

As the title says, over the last two days Thunderbird won't do SMTP authentication to Outlook. It has worked happily for years and nothing at my end has changed. I've the latest version of Thunderbird - 140.15.0esr (64-bit) - and this is Windows 11. It works happily from the Outlook desktop so the password is correct. The authentication method is OAth2 and connection security is STARTTLS. Server is smtp.office365.com and port 587. Anyone else having issues? Presumably MS have changed something (again) Has anyone any suggestions on how to resolve?

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