Several times I get emails from my own domain which is actually not registered, it can also be called a spoof email. Finally I found a solution for this problem, namely by disabling the mail function in the PHP configuration.

Here’s the guide :

Login to Plesk, click Subscriptions – domain name – PHP Settings and scroll down to the Additional configuration directives field, fill it with disable_functions = mail, then click OK.

I also disabled the Sendmail function (applicable in its entirety) :

Login to Plesk, click Tools & Settings – Mail Server Settings – Disable the Allow user and scripts to use Sendmail option and then click OK.

Or if you only want the type of service (Service Plans):

Login to Plesk, click Service Plans – service type name – Mail – Disable the Allow using Sendmail for scripts and users on this subscription option and then click Update & Sync.

Or if you only want the subscription type (Subscription):

Login to Plesk, click Service Plans – Subscriptions – select a domain name – Outgoing Mail Control – Subscription – Change Limit – Disable the Allow using Sendmail for scripts and users on this subscription option and then click OK.

After a few days the email did not appear again. Thank you.