"Domain is owned by another user" when adding a domain to an account

Symptoms

When adding a domain to your cPanel account, you receive the following error:

The domain “domain.tld” may not be created by “user” because “domain.tld” is already 
owned by another user."

Description

This occurs if the domain has already been added to another user's account or added to the "system" user file.

Workaround

You will need to find where the domain is added and remove it to proceed.

1. Connect to your server using SSH as the root user.

2. Run the following command to search for the domain name, replacing 'domain.tld' with the domain you wish to add:

   grep domain.tld /etc/userdomains /var/cpanel/users/*

3. If the domain is listed as being owned by a different user, it can be removed from the tools within that user's cPanel:

   [root@hostname]# grep domain.tld /etc/userdomains /var/cpanel/users/*
   /etc/userdomains:domain.tld: otheruser
   /var/cpanel/users/otheruser:DNS1=domain.tld

   How to remove an addon domain or subdomain from an account

4. If the domain is listed as being owned by 'nobody' and shows up in the 'system' users file, it must be removed manually:

   [root@hostname]# grep domain.tld /etc/userdomains /var/cpanel/users/*
   /etc/userdomains:domain.tld: nobody
   /var/cpanel/users/system:DNS1=domain.tld

5. Open the following file with your preferred text editor:

   /var/cpanel/users/system

6. Remove the "DNS" line that contains your domain and save the file.

7. Rebuild the domain configuration within cPanel:

   /scripts/updateuserdomains --force

You should now be able to add the domain to the intended account.