ASP.NET "Object reference not set..." error

Question

Hi, I have a website written using ASP.NET. We have a development machine and a deployment server.
The site works great on the development machine, but when is transfered (using simple FTP Upload) generates strange behavior. It starts working just fine, but after a while stops working and throws an exception "Exception: Object reference not set to an instance of an object.".
The deal is that the absolute path of the website on the development machine is different than on the deployment server (and why should they be similar?) and the exact error is:

Exception: Object reference not set to an instance of an object. at SOMEPROJECT_Objects.Player..ctor(Int32 PlayerID) in C:\inetpub\wwwroot\SOMEPROJECTSolution\ALLPROJECT\SOMEPROJECT_Objects\Player.cs:line 123 at SOMEPROJECT_GameLayer.M_Game.PlayerActiveGame(Int32 PlayerID) in C:\inetpub\wwwroot\SOMEPROJECTSolution\ALLPROJECT\SOMEPROJECT_GameLayer\M_Game.cs:line 85 at Web.getsms.Page_Load(Object sender, EventArgs e) in C:\inetpub\wwwroot\SOMEPROJECTSolution\ALLPROJECT\SOMEPROJECT-sms\Web\getsms.aspx.cs:line 59

The address that it is looking for is the address on the DEVELOPMENT machine, where as the site now resides on the deployment server.

Any ideas why this happens would be appreciated.

Thanks, Roman

Answer 1

Unfortunately we're not going to be able to help much at this point until you post the relevant code.

You don't need to worry about the path though. That path is only being shown because you built the assembly on your dev machine and then moved it to the server. It happens quite frequently. It's not the source of your issue.

Answer 2

It is correctly telling you where to find the problem in the source code in the location it was last compiled from. You don't normally deploy all of your source to a production machine.

Go back to the development machine and examine the lines of code it is pointing to, and you should be able to determine which object is null that it is complaining about.

Answer 3

I have exactly the same problem! Is there any solution yet?

[NullReferenceException: Object reference not set to an instance of an object.]
   ProjectManager.normal.Page_Load(Object sender, EventArgs e) in D:\User\Projects\ProjectManager\ProjectManager\normal.Master.cs:35
   System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +24
   System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +41
   System.Web.UI.Control.OnLoad(EventArgs e) +131
   System.Web.UI.Control.LoadRecursive() +65
   System.Web.UI.Control.LoadRecursive() +190
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2427

This error occurs only when "published"...

The code says:

using System;

using System.Collections; using System.Configuration; using System.Data; using System.Linq; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.HtmlControls; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Xml.Linq; using MySql.Data.MySqlClient;

namespace ProjectManager { public partial class normal : System.Web.UI.MasterPage { protected void Page_Load(object sender, EventArgs e) {

        if (!IsPostBack)
        {
            cbYear.Items.Add(System.DateTime.Now.Year.ToString());
            cbYear.Items.Add(System.DateTime.Now.AddYears(1).Year.ToString());
            cbYear.SelectedItem = cbYear.Items[cbYear.Items.IndexOfText(System.DateTime.Now.Year.ToString())];
            Session["year"] = cbYear.SelectedItem.Text.ToString();

        }
        else
        {
            Session["year"] = cbYear.SelectedItem.Text.ToString();
        }
        lName.Text = Session["username"].ToString();
        if (Convert.ToInt32(Session["admin"]) == 1)
        {
            ASPxMenu1.Visible = true;
        }
        else
        {
            ASPxMenu1.Visible = false;
        }
    }

    protected void cbYear_SelectedIndexChanged(object sender, EventArgs e)
    {

    }
}

}

Line 35 is:

lName.Text = Session["username"].ToString();

Solutions please! ;-)