I found the reason why. It is because the default window has rules. The windows can't be deleted until the rules associated with them are deleted first. The rules can accessed through View Management.
... this is also the wrong community to be posting ServiceDesk related questions.
This is the community for EndPoint Manager (previous - LANDesk Management Suite) - so "apples to your oranges" as it were.
Here, this should help with any possible naming confusion I hope -- Ivanti Product Names & Acronyms .