TLS1.0 and TLS1.1 support will be terminated.

From October 15, 2020, Office 365 (including Primary Mail Service) will not be able to use the older encryption methods (TLS1.0 and TLS1.1).

Older software and older mobile devices (including smartphones) that do not support TLS1.2 will not be able to connect. If you are unable to connect after this date, please check this point and update your software or change your device if necessary.