I am doing the tutorial at the moment for creating a site from scratch.

I get to the end of step one where I have to add the Logo article information in the CMS and as soon as I have created this when I go back to look at the Home page I get the following error;

Server Error in '/' Application.
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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.]
Kentico.CMS.TreeEngine.TreeNode.NewInstanceFromDataRow(DataRow dataRow, String className, TreeProvider existingTreeProvider) +217
Kentico.CMS.TreeEngine.TreeProvider.SelectSingleNode(String path, TreePathTypeEnum pathType, String className, Boolean selectOnlyPublished) +1042
Kentico.CMS.ContentEngine.ContentProvider.GetSingleNodeContent(String path, TreePathTypeEnum pathType, String className, String transformationName, Boolean selectOnlyPublished, Int32 checkPermissionsForUserId) +71
Kentico.CMS.CMSControls.CMSViewer.GetContent() +350
Kentico.CMS.CMSControls.CMSViewer.BuildFormat() +2259
Kentico.CMS.CMSControls.CMSViewer.OnLoad(EventArgs e) +17
System.Web.UI.Control.LoadRecursive() +47
System.Web.UI.Control.LoadRecursive() +131
System.Web.UI.Control.LoadRecursive() +131
System.Web.UI.Control.LoadRecursive() +131
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1061




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Version Information: Microsoft .NET Framework Version:2.0.50727.42; ASP.NET Version:2.0.50727.42

I have followed the instructions exactly and can't work out why this is happening. As soon as I delete the article the page is visible again?