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Thunderbird (102.5.0) suddenly stops showing MS Exchange account and I'm given the following error: "AADSTS900561: The endpoint only accepts POST requests. Received a GET request."

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  • Last reply by christ1

Zat
Zat
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I've been successfully using TB for years as my single email application for viewing both my personal Gmail email and (with Owl) my Microsoft Exchange business email. However, suddenly the MS Exchange account has stopped loading on start-up and the following error message is provided: "AADSTS900561: The endpoint only accepts POST requests. Received a GET request." Outlook is painful to work with and I really need to access my business email ASAP. Any assistance would be greatly appreciated.

I've been successfully using TB for years as my single email application for viewing both my personal Gmail email and (with Owl) my Microsoft Exchange business email. However, suddenly the MS Exchange account has stopped loading on start-up and the following error message is provided: "AADSTS900561: The endpoint only accepts POST requests. Received a GET request." Outlook is painful to work with and I really need to access my business email ASAP. Any assistance would be greatly appreciated.

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christ1
christ1
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Try to allow cookies in Thunderbird for https://login.microsoftonline.com and https://autologon.microsoftazuread-sso.com.

Check the article at https://support.mozilla.org/en-US/kb/automatic-conversion-google-mail-accounts-oauth20 and follow the instructions in section "How to avoid or correct an OAuth failure caused by rejected cookies".

Modified by christ1