Mail delivery failed: returning message to sender

[kwaslee]

hi team

please help me am trying to send email i got bouncing error .see below error;

554 Your access to this mail system has been rejected due to the sending
MTA's poor reputation. If you believe that this failure is in error, please
contact the intended recipient via alternate means.

[Irithori]

The error is spelled out clear:
The recipient mailserver doesnt like your mailserver.
Probably, because your mailserver sends spam.

[mikesd]

The error is spelled out clear:
The recipient mailserver doesnt like your mailserver.
Probably, because your mailserver sends spam.

It could be just because that it's not a registered name server. Or because it resolves an ip instead of a name.

You can set up sendmail to send via your ISP.

[myne]

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

Unrouteable address

[hans51]

assuming you use postfix
for your outgoing mail to be accepted/welcome by global recipients,
your senders IP needs to resolve to the proper domain name

your name server needs to be properly configured for reverse lookup

a command line

host aaa.bbb.ccc.ddd (your IP)
should result in your domain name being shown

and a dig your_domain.name
should show correct MX records

in modern mail filter systems/spam systems that part is the easiest to reject spammers as they often use incomplete mail configurations.

also make sure your server IP is in no blacklist
just use your IP and google
that will show if your IP known as spammer or hacker IP and listed in various blacklists.