I cannot enable remote Mail server in Tools and Settings->External SMTP Server, the following error appears:
Error: sh: 1: /opt/psa/admin/bin/msmtpmng: not found
MSMTP relay is not installed on the server.
According to documentation:
To use the external SMTP server:
Uninstall the Panel mail server and install the SMTP client: In Tools & Settings > Updates and Upgrades > Add/Remove Components > Mail hosting features select MSMTP relay only mail server (SMTP client) instead of the selected mail server.
Install MSMTP relay using autoinstaller:
# /opt/psa/admin/sbin/autoinstaller ..................... Primary components list / mail =============================================================================== Select the components you want to install: Different mailservers 6. ( ) Postfix mailserver 7. ( ) Qmail mailserver 8. (*) MSMTP relay only mailserver (SMTP client)