Content with id was not found for ContentReference.RootPage

Hi all, 

We have a 2 websites with different code bases and structure. Site1 has a custom content provider that we want to implement in Site2. This custom content provider works fine in Site1.

However, when the code for the provider is copied over to Site2, it compiles ok but at run-time errors out when trying to create a folder under the rootpage. 

For additional info, we are using en-AU as Site2's default language and it also has custom routing in it - not sure if these have any bearing on why we are seeing this error.

Any ideas what might be causing this error and how we can fix it? 

Content with id 1 was not found

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: EPiServer.Core.PageNotFoundException: Content with id 1 was not found

Source Error:

Line 51: 		private ContentReference CreateRootFolder(string rootName, Guid rootGuid)
Line 52: 		{
Line 53: 			_contentRootService.Register<ContentFolder>(rootName, rootGuid, ContentReference.RootPage);
Line 54: 
Line 55: 			var fieldRoot = _contentRootService.Get(rootName);