Object Reference not set to an instance of an object

[Lukapotamus]

Hi All,

I have a problem with a .net website I am creating, it is written in C#.

The error occurs on one of the forms, I can edit the form and click the update button when I first go to the page and everything works fine, but if I visit the page and wait for about 2 -5 minutes and then try editing the form and clicking the update button I ge this error;

/******************Error Starts Here******************/

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 80: protected void imgUpdateDetails_Click(object sender, EventArgs e)
Line 81: {
Line 82: SessionManager.CurrentBusinessClubMember.BCMListingDetails.BusinessClubMemberID = SessionManager.CurrentBusinessClubMember.ID;
Line 83: SessionManager.CurrentBusinessClubMember.BCMListingDetails.Address1 = editaddressline1.Value;
Line 84: SessionManager.CurrentBusinessClubMember.BCMListingDetails.Address2 = editaddressline2.Value;


Source File: d:\Sites\demelzabusinessclub.co.uk\public_html\Website\ListingDetails.aspx.cs Line: 82

Stack Trace:

[NullReferenceException: Object reference not set to an instance of an object.]
DemelzaBusinessClubSite_ListingDetails.imgUpdateDetails_Click(Object sender, EventArgs e) in d:\Sites\demelzabusinessclub.co.uk\public_html\Website\ListingDetails.aspx.cs:82
System.Web.UI.WebControls.LinkButton.OnClick(EventArgs e) +111
System.Web.UI.WebControls.LinkButton.RaisePostBackEvent(String eventArgument) +79
System.Web.UI.WebControls.LinkButton.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +10
System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +13
System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +175
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1565


Version Information: Microsoft .NET Framework Version:2.0.50727.5444; ASP.NET Version:2.0.50727.5420


/******************Error Starts Here******************/

It looks to be something wrong with the session ID and I thought it could be something to do with timeout issues but im not sure, please could someone help.

Kind Regards
Luke