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: 


Line 16:         End If
Line 17: 
Line 18:         If Request.ServerVariables.Item("HTTP_USER_AGENT").ToLower().Contains("mobile") Or _
Line 19:             Request.Browser.IsMobileDevice Then
Line 20:             Page.MasterPageFile = "~/mobile/Default.master"

Source File: E:\Inetpub\wwwroot\RegistrarCMS\App_Code\UserPageModule.vb    Line: 18

Stack Trace: 


[NullReferenceException: Object reference not set to an instance of an object.]
   UserPageModule.Page_PreInit(Object sender, EventArgs e) in E:\Inetpub\wwwroot\RegistrarCMS\App_Code\UserPageModule.vb:18
   System.EventHandler.Invoke(Object sender, EventArgs e) +0
   System.Web.UI.Page.OnPreInit(EventArgs e) +2057548
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +521

Version Information: Microsoft .NET Framework Version:2.0.50727.832; ASP.NET Version:2.0.50727.832