Error 530 validating sender
There can be several causes for dsn error code 5.7.1, for which solutions are provided later in this topic.
There's reasons you might get these error messages.
ASSP therefore provides a "Second SMTP Listen Port" .
Use the syntax: mydomain.com= must be the hostname:port or ip-address:port of the MTA which is used to verify 'RCPT TO' addresses with a VRFY command! You have to enable the SMTP 'VRFY' command on your MTA - the 'EXPN' command should be enabled! If you have configured LDAP and enabled and ASSP finds a VRFY entry for a domain, LDAP search will be done first and if this fails, the VRFY will be used.
default: 530 Relaying not allowed default Local Host: Default Local Host - If you want to be able to send mail to local users without a domain name then put the default local domain here.
Last updated 2015-10-23 Have you ever sent an email message in Outlook or Outlook Web app and received an Exchange NDR error message about why your email couldn't be sent?
These addresses will (necessarily) bypass Griplist, IP Limiting, Delaying, Penalty Box, SPF, DNSBL & SRS checks unless the IP can be determined by (ISP Connecting IP). content Only Re: Regular Expression to Identify Forwarded Messages - Put anything here to identify messages which should bypass PB, Sender Validation, Griplist, IP Limiting, Delaying, SPF, DNSBL & SRS checks.
relay Port: Relay Port - Tell your mail server to connect to this port as its smarthost / relayhost.
For example: 225 Note that you'll want to keep the protected from external access by your firewall.
So VRFY could be used for LDAP backup/fallback/failover!
If you have configured ) if the VRFY is successful.
Not all ISPs will allow their customers to connect to your SMTPport.