When you first upload the MailWizz files to your server (usually the

Before you start the installation, ensure your server meets MailWizz's requirements. It works best on:

If you need to update or change your license key on an already installed version: Log into your MailWizz (not the customer area). Enter the new code and click Save Changes Troubleshooting Tips Invalid Code

On the left-hand sidebar, navigate to > Application . Look for the License / Purchase Code field. Replace the old key with your new purchase code. Scroll to the bottom and click Save Changes . Method B: Via the Database (Advanced)

Ensure your server has cURL enabled in PHP. Ask your hosting provider to ensure outbound traffic on ports 80 and 443 is open, and that it is not blocking ://mailwizz.com . Error: "License already in use on another domain"

The license key is required at the very first step of the web installer. Access Installer : Upload the MailWizz files to your server and navigate to ://yourdomain.com in your browser. Welcome Screen : On the first screen, you will be prompted for License Information Select Source

Double-check that there are no leading or trailing spaces when you paste the code. Connection Errors:

<?php define('MW_LICENSE_KEY', 'YOUR-ACTUAL-LICENSE-KEY');

Sometimes, the process isn't smooth. If you receive an error like or "Connection timed out," here is how to fix it.

Should return HTTP 200.

Sometimes you need to change your license key—for example, after moving to a new domain, renewing an expired license, or switching from a developer license to an extended one.

If you encounter issues during the license key installation process, here are some common problems and solutions:

Now, let's get to the core of the process. Choose the path that fits your hosting environment.