By setting up your own domain, the recipients will see a customer domain as the mailing address in the tracking or opt-in confirmation links. This has the advantage that an external service provider is not visible at first glance. If you want to use your own customer domain in a account, the name server of your domain has to be updated. This involves changes in the DNS configuration, whereby the domain will refer to the system´s servers in the future. The DomainCheck checks the entered domain for possible integration into a account.