Test Message from outlook fails: The server responded: 450 4.7.1 Client host rej

[expansity]

Hi guys,

Everything works sending messages from/to webmail.

I try setting up my mail account in Outlook with the above error.

Please assist

[adamjedgar]

Can you post the full error message...the crucial part for someone to help problem solve this is missing..

What does the message say after "reg"?

Is it something like " rejected: unverified address " ?

[expansity]

See error:

Server error: '450 4.7.1 Client host rejected: cannot find your hostname, [x.x.x.x]'

[expansity]

For those having same error, I solved my issue as follows:
1. When rebuilding Postfix Configuration, only tick: ClamAV, Amavis & Spamassassin, AND Install DKIM & SPF
2. Restart all mail server services

I can now send and receive emails from Outlook.

[evansa]

also ask IP provider to create rdns/PTR to resolve from your IP to your server hostname