So I have had to change from 123-reg to one.com as my email service provider as 123-reg have removed their 'catch-all' forwarding option.
Moving to One.com was easy and quick to do. BUT I am having issues sending emails through their SMTP server.
The error message I get is
User [simon@dancingbear.me.uk] not authorized to send on behalf of
I am connecting using STARTTLS and as I said POP collection is not a problem. Does anyone have any ideas?
The dia