I agree it's a very generic error, typically you can get a bit more of a clue by looking down the rest of the stacktrace. All it means is that something tries to read a value from an object, expecting it to be there, but the object is not initialised for some reason e.g.

dim firstnum as integer

dim secondnum as integer

dim divisionresult as integer=firstnum\secondnum

This code will work fine in most cases, but if the secondnum variable is zero, then a division by zero error will happen and divisionresult will not initialise.

Where are you getting the error, in corecode, or in one of your own modules?

Dear all

I have a DNN installation www.crystalbuilder.com.  I created another parent portal www.angusbeare.com from this. However, when I try to edit the site settings I get the following error.  I'm using a company in the US to host my sites (I'm in the UK) but they can't seem to help and I don't have access to IIS to tweak or check security settings.  It all works fine on my laptop running locally.  I think it must be either a file or DB permissions issue.  Can't find anything on the web or DNN forums.

Server Error in '/' Application.

---

Object reference not set to an instance of an object.

My web.config has

<configuration>
   <system.web>
       <compilation debug="true"/>
   </system.web>
</configuration>

and the stack trace is

NullReferenceException: Object reference not set to an instance of an object.]
   DotNetNuke.Modules.Admin.PortalManagement.SiteSettings.cmdUpdate_Click(Object sender, EventArgs e) +1337

[ModuleLoadException: Error: Site Settings is currently unavailable.]
   DotNetNuke.Services.Exceptions.Exceptions.ProcessModuleLoadException(String FriendlyMessage, PortalModuleBase ctrlModule, Exception exc, Boolean DisplayErrorMessage) +467
   DotNetNuke.Services.Exceptions.Exceptions.ProcessModuleLoadException(PortalModuleBase ctrlModule, Exception exc) +82
   DotNetNuke.Modules.Admin.PortalManagement.SiteSettings.cmdUpdate_Click(Object sender, EventArgs e) +2756
   System.Web.UI.WebControls.LinkButton.OnClick(EventArgs e) +105
   System.Web.UI.WebControls.LinkButton.RaisePostBackEvent(String eventArgument) +107
   System.Web.UI.WebControls.LinkButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +7
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +11
   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +174
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +5102

[PageLoadException: Error: Site Settings is currently unavailable.]
   DotNetNuke.Services.Exceptions.Exceptions.ProcessPageLoadException(Exception exc, String URL) +354
   DotNetNuke.Framework.PageBase.Page_Error(Object Source, EventArgs e) +375
   System.Web.UI.TemplateControl.OnError(EventArgs e) +105
   System.Web.UI.Page.HandleError(Exception e) +73
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +6944
   System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +154
   System.Web.UI.Page.ProcessRequest() +86
   System.Web.UI.Page.ProcessRequestWithNoAssert(HttpContext context) +18
   System.Web.UI.Page.ProcessRequest(HttpContext context) +49
   ASP.default_aspx.ProcessRequest(HttpContext context) +29
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +154
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +64

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

This has stopped progress.  Unless I can find an answer I will have to forget using DNN.