Question

This error pops up whenever I attempt to view a webpage in preview mode using the sitecore content management system:

Object reference not set to an instance of an object.

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:

System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[NullReferenceException: Object reference not set to an instance of an object.]
NLC.Website.layouts.SubLayouts.Body_Header.Page_Load(Object sender, EventArgs e) in D:\src\tfs2010\Sitecore.ATS\Dev\1.0\NLC.Website\layouts\SubLayouts\PageStructure\Body-Header.ascx.cs:52

System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +24
System.Web.UI.Control.LoadRecursive() +70
System.Web.UI.Control.LoadRecursive() +189
System.Web.UI.Control.LoadRecursive() +189
System.Web.UI.Control.LoadRecursive() +189
System.Web.UI.Control.LoadRecursive() +189
System.Web.UI.Control.LoadRecursive() +189
System.Web.UI.Control.LoadRecursive() +189
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3063

I am new to using this program and am currently experimenting with it. My knowledge is limited in regards to programming but I am willing to learn! So please if you have any advice at all, I am all ears!

Answer 1

Check line 52 of NLC.Website\layouts\SubLayouts\PageStructure\Body-Header.ascx.cs for an object which is null. In Sitecore sites, this is sometimes an Item that does not exist.

See the following SOF question for more information on NullReferenceException and debugging it.

What is a NullReferenceException, and how do I fix it?