can not send email,
An error occurred：VersionNotSupported
That could mean your eg: current license key does not cover the version of eM Client you are trying to use,
Or could be you are running an eg: older legacy version of eM Client that is longer supported by modern mail servers so it also fails to send and might need upgrading.
Has this sending mail issue happened since you upgraded ? Or did it suddenly happen ?
Also what version of eM Client do you have ?
Also when you go to “Menu / Help / License does it say activated ?