can receive email but cannot send

[th3infekt3d]

this is the settings when I installed it


=== Informations required to build your server ===
The installer requires 2 pieces of information:
1) the sub-domain that you want to use to access Sentora panel,
- do not use your main domain (like domain.com)
- use a sub-domain, e.g panel.domain.com
- or use the server hostname, e.g server1.domain.com
- DNS must already be configured and pointing to the server IP
for this sub-domain
2) The public IP of the server.


Enter the sub-domain you want to access Sentora panel: mail.mydomain.com

The public IP of the server is XX.XXX.XX.XXX. Its local IP is XXX.XXX.X.XXX
For a production server, the PUBLIC IP must be used.
Enter (or confirm) the public IP for this server: XX.XXX.XX.XXX

OK: DNS successfully resolves mail.mydomain.com to XX.XXX.XX.XXX

All is ok. Do you want to install Sentora now (y/n)?