Outlook DesktopApp does not sent Emails for hotmail account

[josefbecker_hotmail]

I am using Outlook desktop app. Since today it is not possible to sent mails for hotmail.com or outlook.de email accounts. For an web.de account it is possible to sent mails using Outlook desktop app. By using the web UI I can sent mails from my hotmail account.

When I try to sent an Email  Outlook is restarting, the message is gone.

But an Outlook meeting can be sent.

[#2]

This seems to have a lot in common with the thread I opened yesterday at
https://techcommunity.microsoft.com/t5/outlook/outlook-office-2019-crashes-when-send-of-from-clicked....
Is it just the Send button that results in the crash, or also (like for me) the From button?

[#3]

@thelordgiveth

It is the Send button and the From Button. You mentioned, that you did a repair. In my case Repair button is disabled for hotmail.com and outlook.de acounts. So I tried to delete and add the account in my Outlook app. But that does not change anything. I also disabled all Add-Ins.

And I tried to disable "Exchange-Cache-Modus". But for unkown reasons that is not possible.

I can disable the setting and I get a message that this was successful and the change will be active after restart outlook. But after restart the setting is unchanged.

Furthermore I created an alias as discribed here:

https://support.microsoft.com/de-de/office/das-versenden-von-e-mails-%C3%BCber-verbundene-konten-von...

I tried a lot, but nothing solves my problem.