Check remote servers when validating email addresses
It could be implemented with another postqueue command option that connects to the verify daemon, perhaps with a flag that says don't talk to remote servers.This runs an email address through Postfix's "routers" and agents that know how to deliver mail.This functionality is very useful for doing "real time" email address validation when email addresses are posted from web forms.-- Mike Cardwell https://https://Open PGP Key 35BC AF1D 3AA2 1F84 3DC3 B0CF 70A5 F512 0018 461F XMPP OTR Key 8924 B06A 7917 AAF3 DBB1 BF1B 295C 3C78 3EF1 46B4 you should avoid that for two reasons: * automated form submits may lead in blacklisting because it results in a delivery attempt behind the scenes if your webserver is able to execute shell commands the setup is highly questionable Address verification is always a guess. Executing the following Perl from a CGI script is completely safe: my $valid = eval ; -- Mike Cardwell https://https://Open PGP Key 35BC AF1D 3AA2 1F84 3DC3 B0CF 70A5 F512 0018 461F XMPP OTR Key 8924 B06A 7917 AAF3 DBB1 BF1B 295C 3C78 3EF1 46B4 beside postfix verify, may use a script to build a "table" with valid recipients i ve tested some stuff for other reasons https://sys4.de/de/blog/2014/03/02/recipient-verification-tls-mandatory-modus/Best Regards Mf G Robert Schetterer -- [*] sys4 AG 49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Marc Schiffbauer Aufsichtsratsvorsitzender: Florian Kirstein i doubt: https://github.com/Exim/exim/wiki/Verificationfor a formal check without verification you don't need a MTA - the MX record is not mandatory if not present the MTA falls back to the A record!
If your organization has its own email server (also called on-premises server), you must set up connectors to enable mail flow between Office 365 and your email server.
Comodo will send a mail to this address which contains a validation link and a unique validation code.
You can confirm domain control by clicking the link and following the instructions on the page that this link opens.
This article helps if you want to validate your connectors at a different time, or if you want to understand more about the process.
Use built-in connector validation to test whether a connector is set up correctly and fix any mail flow issues before you turn the connector on.