my cwp sent emails but it can't receive them, the IP is not in any spam list , but now here is the bounce email: This is the mail system at
host vps55.mosalam.com.
I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.
For further assistance, please send mail to the postmaster.
If you do so, please include this problem report. You can
delete your own text from the attached returned message.
The mail system
<ali@generalprinteg.com>: host mail.generalprinteg.com[178.63.195.98] said: 554
5.7.1 Service unavailable; Client host [178.63.195.100] blocked using
zen.spamhaus.org; Error: open resolver;
https://www.spamhaus.org/returnc/pub/172.68.49.210 (in reply to RCPT TO
command)
and the spamhouse link said:
Your email has bounced back from the recipient
If you are viewing this page, you have likely sent an email that was not delivered to the recipient. In the resulting bounced email message you have found and clicked this link: https://www.spamhaus.org/returnc/pub/172.68.49.210
The problem doesn’t relate to your email set-up.
Why has my email not been delivered?
The problem is with the recipient’s email server configuration.
This is not due to an issue with your email set-up.
It is not because you are listed on one of our blocklists.
also here is the log :