I have a umbraco v 4.11.5 (Assembly version: 1.0.4807.33359) 

Database msSQL 2008 10.0.1600.22 

• When i create a new page the preview does not work.
• When i save the page the previev does not work.
• When i publish the page the previev works.
• When i unpublish the page again the prewiev wont work

Is this a bug, or am i missing something?

I get this error when trying to preview an unpublished node.

Server Error in '/' Application.
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.]
   umbraco.page.attrValue(XmlNode node, String attributeName) +10
   umbraco.page.populatePageData(XmlNode node) +157
   umbraco.page..ctor(XmlNode node) +156
   umbraco.presentation.templateControls.ItemRenderer.GetFieldContents(Item item) +209
   umbraco.presentation.templateControls.ItemRenderer.ParseMacros(Item item) +89
   umbraco.presentation.templateControls.Item.OnLoad(EventArgs e) +32
   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.Control.LoadRecursive() +189
   System.Web.UI.Control.LoadRecursive() +189
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3177

Tanks, for this grest forum.

René