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"Unable to log in at server"

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This morning, I repeatedly received an "Authentication failed when connecting to outlook.office365.com" error. I removed the Outlook account from Thunderbird hoping to solve this by reconnecting and starting from scratch. Upon entering my email and password, my configuration is successfully located in the Mozilla database, but upon selecting the IMAP configuration and after a brief password check, I received the error message "Unable to log in at server. Probably wrong configuration, username or password". Is this an issue on Outlook's end, or is something not set up properly?

This morning, I repeatedly received an "Authentication failed when connecting to outlook.office365.com" error. I removed the Outlook account from Thunderbird hoping to solve this by reconnecting and starting from scratch. Upon entering my email and password, my configuration is successfully located in the Mozilla database, but upon selecting the IMAP configuration and after a brief password check, I received the error message "Unable to log in at server. Probably wrong configuration, username or password". Is this an issue on Outlook's end, or is something not set up properly?

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Possibly due to service outage https://downdetector.com/status/outlook/

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