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Thunderbird Sending of the message failed.Unable to authenticate to Outgoing server (SMTP) smtp.office365.com.

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Effective yesterday, I started to receive the following error message when trying to send and emails using Microsoft email account:

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)'.

I verified SMTP Settings; they are correct and are as follows:

Server Name: smtp.office365.com Port: 587 Connection Security: STARTTLS Authentication Method: OAuth2 User Name: complete email account

I am having this identical error occurring on multiple Microsoft email accounts installed in Thunderbird, on the same computer. I uninstalled and reinstalled each email account and continue to receive the same error message on each email account.

Currently Installed Version of Thunderbird: 110.0b3 (64-bit)

Operating System: Windows Edition: Windows 11 Pro Version: 22H2 Installed on: 11/8/2022 OS Build: 22621.1194

The following was the last Update Installed on February 4, 2023, from Microsoft: 2023-01 Cumulative Update Preview for .NET Framework 3.5 and 4.8.1 for Windows 11, version 22H2 for x64 (KB5022404)

Please advise

Effective yesterday, I started to receive the following error message when trying to send and emails using Microsoft email account: '''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)'.''' I verified SMTP Settings; they are correct and are as follows: Server Name: smtp.office365.com Port: 587 Connection Security: STARTTLS Authentication Method: OAuth2 User Name: complete email account I am having this identical error occurring on multiple Microsoft email accounts installed in Thunderbird, on the same computer. I uninstalled and reinstalled each email account and continue to receive the same error message on each email account. Currently Installed Version of Thunderbird: 110.0b3 (64-bit) '''Operating System:''' Windows Edition: Windows 11 Pro Version: 22H2 Installed on: 11/8/2022 OS Build: 22621.1194 The following was the last Update Installed on February 4, 2023, from Microsoft: 2023-01 Cumulative Update Preview for .NET Framework 3.5 and 4.8.1 for Windows 11, version 22H2 for x64 (KB5022404) Please advise