Hello, when I send mails using PHP method, Gmail shows "mail send via myserver.com". 

 

The issue is related with this:

https://stackoverflow.com/questions/42182263/how-to-remove-via-from-email-using-mail

Is it possible remove this, using for example the "Additional Parameters" in PHP?

Thanks.

That controls the additional parameters as you are asking. As for removing the header, make sure you read the article and take all of the appropriate steps. We set "From" as your outgoing address, and "Reply-To" as the user's address (or your incoming address, depending upon the context) so make sure your email configuration is correct. And look into the SPF and DKIM configurations as mentioned.