Question : Plesk and Default Page

I am working on a dedicated server which uses Plesk. The server contains a single website.

Works - http://mydomain.com
Default Page - http://www.mydomain.com
Default Page - http://server-ip-address

How do I fix this?

Answer : Plesk and Default Page

I have found the solution, under "IP Addresses" the domain was not specified as the default domain.