1. Log into your SiteWorx account. (e.g.: www.example.com:2443/siteworx/ )
2. Under SiteWorx Menu, click the Hosting Features menu item if it is not already open.
3. Click the Domain menu item and then choose the Subdomain option.
. Select the appropriate domain name you wish to delete under the Existing Domains
Click the Delete
A confirmation window will appear. Click again on the Delete
You should see a success message popping up, notifying you that your subdomain has been removed.