Hi @sakura_snow_blossom ,
Regarding the “MSExchange Mitigation Service” error, you are correct that this error occurs because a temporary Exchange Server remains and there is no actual harm. Since there are no mailboxes left on the temporary server, you can safely ignore this error.
As for the SSL certificate, it is recommended that you do not delete self-signed certificates in ExchangeBackEnd. Therefore, it is advisable to restore the ExchangeBackEnd certificate. However, if you have already deleted it, you can create a new self-signed certificate and bind it to the ExchangeBackEnd website.
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