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The STAT command did not succeed. Error getting number and sizes. Mail server outlook.office365.com responded: Server Unavailable. 21

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Problem just started today 11-25-2024... Using Thunderbird 128.4.3esr (64-bit)...

Get error message in Thunderbird:

"The STAT command did not succeed. Error getting number and sizes. Mail server outlook.office365.com responded: Server Unavailable. 21"

Do receive the email on an iPad and an iPhone. Not sure if this is a Microsoft365 issue or Mozilla Thunderbird issue? Have other email accounts on Thunderbird and they are coming in fine.

Problem just started today 11-25-2024... Using Thunderbird 128.4.3esr (64-bit)... Get error message in Thunderbird: "The STAT command did not succeed. Error getting number and sizes. Mail server outlook.office365.com responded: Server Unavailable. 21" Do receive the email on an iPad and an iPhone. Not sure if this is a Microsoft365 issue or Mozilla Thunderbird issue? Have other email accounts on Thunderbird and they are coming in fine.

All Replies (3)

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Hello there We have read the question. We try to help


Try to reset all passwords of the recent accounts ,disconnect and reconnect all accounts and reinstall all connected accounts to Thunderbird.like Gmail , Outlook. Try to do this manually .also look for bad add-ons and replace or delete them, oke. The software has been crashed. It is a lot of work So take youre time to do that.


Greetings Firefox volunteer

Helpful?

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Helpful?

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Hello there

This error can solve itself in days with normal use of the software.

Greetings Firefox volunteer

Helpful?

Yi tambaya

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