Important! Email in CRM feature stops working after moving Bitrix24 from Cloud to On-premise editions.
Email feature in Bitrix24 Cloud version operates with official Bitrix24 mail server. However, Bitrix24 On-premise uses your custom email server. Such server must be configured correctly, with specific sender-associated SMTP server to be used.
Below is the approximate sequence of your actions:
Catch all outbound email using the function
Starting from Bitrix24 version 7.1.3, standard email mechanism can be redefined.
Mechanics are simple: bxmail() function is called anywhere where mail() must be called. Bitrix24 checks inside bxmail() if custom_mail() is defined before calling standard function mail(). Defined custom_mail() replaces mail() function. Accordingly, write the function custom_mail() to redefine sending mechanism.
Configure any MTA (
Mail Transfer AgentMTA — minimally required software needed for receiving and sending emails. Any MTA operates simultaneously with several email protocols: SMTP, POP, IMAP.
) email server, suitable for your objectives.
Employ previously used function custom_mail, troubleshoot outbound emails via configured email server from the required
You can manage email records at the Mailboxes page (Services > Mail > Mailboxes). Be advised, that Bitrix Framework allows creating an unlimited number of email entries.
Note: assistance of software specialists is required to configure email server (as well as system administrator).