Have you added your hostname and startpage in Adminmode? 

Under Admin -> Config -> Manage Website
You need to set sitename and hostname.

Had the same error and it was resolved by doing this. 

Also check so no references exists to pagetypebuilder. In fact remove all the pagetypebuilder dll's you have in your project.

Thank Jens for your Reply.

Actually sitename and hostmane are ok and there aren't any reference to pagetypebuilder dlls too. Still wondering why this is happening. All these came into action after we did the 7.5 upgrade

Do you get this on all pagetypes. I mean is StartPageType the only one working?


Try going to your pagetype in EPiServer Admin and do a "Revert to default". 

Here´s a forumpost about the same error

Yes Jens, I have already gone through the forum post you have shared. "Revert to default" doesn't worked for me either. And also, this error is only appearing in one pagetype. Other pagetypes working fine.

Can you post the top part of your template for the pagetype (Codebehind)? Does the template for the pagetype have same inheritances as other working templates?

Oh and have you checked in db if there are any duplicates?

How do I check duplicates in DB (are you refering to check tblPageType ?)

SELECT *

FROM tblContentType WHERE Name = 'YourPageType'

You could also take a look if the Guid on the pageType in EPiServer admin for your specific pagetype have any duplicates. Maybe it shares guid with StartPageType

Just a wild guess though. :-D

SELECT *
FROM tblContentType WHERE ContentTypeGUID = 'Guid for affected pagetype' 

Thanks Jens for your prompt help. But there isn't any duplicate GUIDs or sharing GUID between 2 types in the DB  

This is the pagetype

[ContentType(GUID = "75A99539-4462-4FCE-A533-3116714157C9",
	DisplayName = "MyPageType",
	Description = "My Page Type",
	Order = 800,
	AvailableInEditMode = true )]
[AvailableContentTypes(Include = new Type[] { typeof(MyPageType1), typeof(MyPageType2), typeof(MyPageType3) })]
[SiteImageUrl]
public class MyPageType : PageBase
{
	
}

public class PageBase : PageBaseAbstract
{
	
}

public abstract class PageBaseAbstract : PageData
{
	
}

And this is the pagetemplate

public partial class MyPageTemplate : PageTemplateBase<MyPageType>
{

}

public abstract class PageTemplateBase<T> : TemplatePage<T> where T : PageData
{

}

Any help ?

Couple of week back we manage to resolve this issue. Root-cause for this problem was, we are using "classic" links (links that has "id" parameter in querystring ) in some part of our solution. By default Episerver 7.5 doesn't support query parameter "ID" (it's a 7.5 breaking change). So, as a solution, we have implement classic routing (using EPiServer.Web.Routing.ClassicLinkRoute) in our application and it's worked.