How to Install PowerMTA & MailWizz:
The Complete 2025 Guide

If you are looking to send over 100,000 emails per day without breaking the bank on services like SendGrid or Mailgun, a self-hosted infrastructure is the only viable solution. The gold standard for this setup is PowerMTA (PMTA) combined with MailWizz.

This guide will walk you through the technical requirements, DNS authentication, and installation steps required to build a high-volume email server.

Step 1: Server Requirements

Before you begin, you need the right hardware. Do not use standard shared hosting. You need a VPS (Virtual Private Server) or a Dedicated Server with port 25 open.

• OS: CentOS 7, AlmaLinux 8, or Ubuntu 20.04 (CentOS is preferred for PMTA).
• RAM: Minimum 4GB (8GB recommended for MailWizz).
• IPs: At least 1 Clean Dedicated IP. For high volume (1M+ emails), we recommend a /29 block (5 IPs) or /24 block (254 IPs) for rotation.

Step 2: DNS Authentication (The Most Critical Step)

You cannot send emails without proper authentication. If you skip this, your emails will go to Spam immediately.

1. A Record

Point your hostname (e.g., server.yourdomain.com) to your server's Main IP.

2. PTR Record (rDNS)

This is configured at your hosting provider level (not your domain registrar). The Reverse DNS of your IP must match your hostname.

3. SPF Record

Add a TXT record to your domain:

v=spf1 ip4:1.2.3.4 -all

4. DMARC Record

Add a TXT record for _dmarc:

v=DMARC1; p=none; rua=mailto:admin@yourdomain.com

Step 3: Installing PowerMTA

Once your DNS is propagated, log in to your server via SSH (using Putty or Terminal).

1. Update System

yum update -y

2. Upload and Install RPM

Upload your PowerMTA RPM file to the server (usually to /usr/src). Then run:

rpm -ivh PowerMTA-5.0r3.rpm

Step 4: Configuring config

The heart of PowerMTA is the config file located at /etc/pmta/config. This is where you define your Virtual MTAs (VMTAs) and IP rotation rules.

    smtp-source-host 1.2.3.4 server.yourdomain.com
    
        max-smtp-out    20
        max-msg-per-connection 50
    

Step 5: Installing MailWizz

MailWizz is the front-end dashboard where you upload contacts and send campaigns. It connects to PowerMTA via SMTP.

1. Install a LAMP stack (Linux, Apache, MySQL, PHP).
2. Create a MySQL database for MailWizz.
3. Upload MailWizz files to /var/www/html.
4. Run the installer from your browser and connect it to your database.