MX Toolbox Errors

Hi,
I have setup a server using this guide - https://www.howtoforge.com/tutorial...-php-pureftpd-postfix-dovecot-and-ispconfig3/

When running MX Toolbox I get a few errors (see attached)

Are these anything to be concerned about? and if so, how would I fix these?

Thanks
Matt

 

You have a DNS problem. I think that www.intodns.com will explain better what to do.

 

Yes, found it, my nameservers was wrong at the domain host.

Thanks for your help.