When you plan to add an extra domain to your Coldfusion supported hosting package you may get following error message
“Error: ColdFusion support is switched off for this website ” Usually we forget to select CF support while adding new domain through the Plesk control panel.

You need to follow the steps below in order to enable CF support for your addon domain.
Steps >>

# Login to the Plesk control panel.
# Click on Domains —Manage hosting
# Go to Website and Domains.
# Click on Hide Advanced operations.
# Click on Website scripting and Security.
# Enable the box for Adobe ColdFusion support and finally click OK…

Now you should be able to add the CF Data Sources for your addon domain using the plesk control panel.