SQL Server 2017 Database mail

Hi

I am installing SQL Server 2017, this is the first time I have installed 2017, and normally I have never had much issue with database mail but this time I keep getting

The mail could not be sent to the recipients because of the mail server failure. (Sending Mail using Account 1 (2019-06-26T16:13:13). Exception Message: Cannot send mails to mail server. (Failure sending mail.). )

I have checked the user permissions, that database mail is enabled, server name is the same as the old SQL server 

I just can see what I am missing this time

Any suggestions gratefully received

Glynn