How to replace SMTP server?

Question

SMTP

Hello, I need to change the default SMTP server to another one. How to do it?
The customer placed hosting on reg.ru, his own SMTP server is provided there, but he did not like it because all sent letters immediately go to spam.
The customer decided to change the SMTP service and first his eyes fell on SendPulse, and then on SendBulls. The first failed, but the second paid. We received the data, but it’s not clear what to do with them and where to insert them.
Before that, the part with the mail did not touch at all. Google doesn't give you what you need.
In general, I’m interested in what solutions to this situation are: where to write those sendbulls mail service data? What SMTP services are worth noticing? Are there ready-made solutions for working with a third-party smtp service?
Sendbuls did not begin to explain anything and answered generally anyhow.

Answer 1

It's funny with you, first they pay then they ask -)
I looked at your sendbulls - in fact you were given a smarthost address with authentication. There is no need to change the MTA itself on the server. You need to configure it to the smarthost issued to you with authentication.
If you need to set up Outlook, for example, for mailings, then someone has already carefully filmed a video for you: https://youtu.be/Uv78yD7L8tA

Answer 2

Put something like msmtp or nullmailer and write the necessary data in their settings file. These utilities will replace the standard sendmail, through which emails are sent from PHP.

Answer 3

If you work on a VPS and you have the ability to install software on linux, then this is a separate tag and a topic with an MTA setting - for example, msmtp (very simple) or postifx (you can google directly on the phrase "installing and configuring msmtp").
If you have shared hosting, then you most likely will not be able to replace the standard mail. In this case, you will need a wrapper, such as PHPMailer

Answer 4

As data from the service, they first sent records that need to be applied to the domain, and then the host, username, password.