Certificate-based connector configuration: Make sure that your on-premises email server is configured to employ a certificate to send out email to Microsoft 365, as well as the Widespread-Title (CN) or Issue Alternate Title (SAN) inside the certificate contains a domain name that you have registered in Microsoft 365, and you've https://bookmarkity.com/story17150576/5-tips-about-mysql-performance-tuning-you-can-use-today