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Won't connect to MS 365 Business account -- is there an alternative to Thunderbird?

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  • 1 has this problem
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  • Last reply by Rambler

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I've been trying to connect TB to my MS 365 Business email account without any luck. I've tried on my macOS Monterey machine and on openSUSE TW 15.3.

After a 30 minute phone call and screen share with MS tech support, they determined that Thunderbird does not connect to their email servers. The Active Directory sign-in logs showed no Thunderbird sign-in attempts from either macOS or Linux platforms even though we tried many times to connect.

Can someone recommend a multi platform (Win, mac, & Linux) email client that works with MS 365 Business?

I've been trying to connect TB to my MS 365 Business email account without any luck. I've tried on my macOS Monterey machine and on openSUSE TW 15.3. After a 30 minute phone call and screen share with MS tech support, they determined that Thunderbird does not connect to their email servers. The Active Directory sign-in logs showed no Thunderbird sign-in attempts from either macOS or Linux platforms even though we tried many times to connect. Can someone recommend a multi platform (Win, mac, & Linux) email client that works with MS 365 Business?

Chosen solution

I appreciate the continued help but have already uninstalled Thunderbird from both platforms and have moved on to Rambox. I don't have this much time and energy to waste on setting up email --either it works or it doesn't.

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Thunderbird. If imap or pop are enabled. They are not by default in M$ mail

Or using an addon for exchange.

Although the authentication method might be an issue, depending on your configuration. https://bugzilla.mozilla.org/show_bug.cgi?id=1528136

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IMAP & POP are both enabled.

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If IMAP, POP and SMTP are enabled, it can be as simple as setting the authentication to OAuth2:

https://office365.mcmaster.ca/reconfigure-mozilla-thunderbird-for-modern-authentication/

but in other cases, it requires more complex settings:

https://eightwone.com/2020/07/01/configuring-exchange-account-with-imap-oauth2/

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I finally got it working. I had to change a setting in the Config Editor:

General.UserAgent.CompatMode.Firefox setting to True (instead of the default False)

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Update: I'm able to retrieve all my email (even custom folders) but cannot send email. I get a password error even though the password is correct. Two more MS tech support agents today (not including tech from yesterday) were unable to get Thunderbird to send email. They deleted & recreated the account from scratch, tried every possible SMTP config possible, double checked my MS 365 Admin settings, etc, but still cannot send email.

At some point I had to get back to work so I abandoned Thunderbird and am now using MS 365 on the web via the Rambox app on both my macOS and Linux systems.

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Chosen Solution

I appreciate the continued help but have already uninstalled Thunderbird from both platforms and have moved on to Rambox. I don't have this much time and energy to waste on setting up email --either it works or it doesn't.