Hi @Maximilian Schäfer,
When i however go to an Account which ran on a Failed Exchange 2007 Account. (Failed to Decomission) It will not Connect and asks Permanantly for a Password. If i click Cancel it will Fail too. I need Help!
Do you mean the Exchange 2007 account is added to the Outlook 2021 client but failed to connect?
If this is the case, it's likely to be an expected behavior considering the fact that Exchange 2007 has reached end of support long ago. Also, according to Exchange Server supportability matrix, even Exchange 2013 is not officially supported to be used together with Outlook 2021, so not to mention it's an Exchange 2007 account.
Do you still need to use the Exchange 2007 account in Outlook client? If yes, you may need to use an earlier version of Outlook like Outlook 2013. If this failed account is no longer needed to be used, you can just delete it from the Outlook profile.
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