While cracked versions of Mailwizz exist that bypass the license key requirement, they are highly discouraged for email marketing software.
The key is still registered to an old domain, sub-domain, or a deleted installation. mailwizz license key work
This key is required during the installation process to authenticate your instance of MailWizz with their licensing server. How Does the License Key System Work? While cracked versions of Mailwizz exist that bypass