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Mozilla Thunderbird email / MS Outlook Link

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  • Last reply by jon115

jon115
jon115
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Hi,

I have a Mozilla Thunderbird email client, which has been linked to my Microsoft Outlook account using IMAP for years, and has operated perfectly well for my personal preferences.

At some point overnight (26th / 27th May) this stopped working and I am now presented with the error message "Sending of password for user xxx@xxxxxxx.co.uk did not succeed. Mail server outlook.office365.com responded: Logon failure: unknown user name or bad password" when trying to download mail.

This is very strange as I can log in directly to my Outlook account using the same user name and password. No settings were changed by me in either Mozilla or Outlook.

For information, I can still send messages from Thunderbird but not now receive them.

Can anyone help, please?

Many thanks.

Hi, I have a Mozilla Thunderbird email client, which has been linked to my Microsoft Outlook account using IMAP for years, and has operated perfectly well for my personal preferences. At some point overnight (26th / 27th May) this stopped working and I am now presented with the error message "Sending of password for user xxx@xxxxxxx.co.uk did not succeed. Mail server outlook.office365.com responded: Logon failure: unknown user name or bad password" when trying to download mail. This is very strange as I can log in directly to my Outlook account using the same user name and password. No settings were changed by me in either Mozilla or Outlook. For information, I can still send messages from Thunderbird but not now receive them. Can anyone help, please? Many thanks.

Chosen solution

Hello again,

I have just found and read Judy's help request of 18th November 2021 and subsequent responses, listed under "Email not flowing from/to Thunderbird via Outlook". It would appear she had the same problem.

Like her, with help from sfhowes and Matt (for which, many thanks), I have changed the authorisation method to OAuth2 (whatever that may mean) for BOTH incoming and outgoing servers - it doesn't work for just the incoming server - and you are presented with a Microsoft dialogue box about granting Thunderbird permission to access their servers.

So, solution found; panic over!

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jon115
jon115 Question owner
more options

Chosen Solution

Hello again,

I have just found and read Judy's help request of 18th November 2021 and subsequent responses, listed under "Email not flowing from/to Thunderbird via Outlook". It would appear she had the same problem.

Like her, with help from sfhowes and Matt (for which, many thanks), I have changed the authorisation method to OAuth2 (whatever that may mean) for BOTH incoming and outgoing servers - it doesn't work for just the incoming server - and you are presented with a Microsoft dialogue box about granting Thunderbird permission to access their servers.

So, solution found; panic over!