Value cannot be null, Parameter name: rootElement

Question

I am getting an error when trying to create and save a page in the Home structure Group of a publication. What does this error mean?

Update: We have a metadata schema for the pages in this publication associated with a particular page template and a mandatory field called "default url" in the metadata schema. This field has a default value of "/" and is populated with the page path on save. This is done using event handler. When a page is saved with default template and saved with our page template for the second time, there is no problem. However, if we use the page template on the first save, the error appears and the default url is not getting populated.

Answer 1

In your templates, check for the parameter schema associated and verify that a specific mandatory value is not empty or null. It may happen in case when you import templates from one environment to another and the item on which template have a dependency (may be a category/keyword or a component link ) has not been imported. You can see parameters in a template either in template builder or in the source tab of the template.

The same scenario applies for the page as well.

Answer 2

I feel the problem with you event handler. The exception you get is thrown because Page.Metadata is empty during creation. I can imagine that your event handler is trying to look up path of the page, but, depending on what way it trying to get data, the data might not yet be there, as this is new page and some properties are only being set after it's actually created, Page.Path is one of them.

Your event handler is probably trying to read Page.Path and generate XML, but as it is null it fails. You probably have this entire block somewhere in try-catch statement and can't even see if your event handler failed.

For future questions, please include entire stack trace and describe your process straightaway, otherwise no one will help you.