Symantec Endpoint Protection Manager 14.x
Any problems with e-mail delivery along its network route prohibit it from being delivered to the recipient's address.
Note: Please be sure to revert the changes made to the conf.properties file and restart the SEPM service again when the password reset procedure is finished.
Please do note, that this workaround is not proven to work in 100% of cases and Symantec does not guarantee this procedure to work.
In case of forgotten password and inability to send the password reset link, the only proven method to re-gain access to the SEPM console, is a database recovery to the last known, working configuration.
Symantec does not assist in password recovery if you cannot recover your password with the Forgot your password? functionality. Please refer to the following TechDocs article --> https://techdocs.broadcom.com/us/en/symantec-security-software/endpoint-security-and-management/endpoint-protection/all/managing-groups-clients-and-administrators/managing-administrator-accounts-v17364367-d1e6/resetting-a-forgotten-password-v16011680-d1e1777.html.