Thanks Chris for your suggestions.

 We did implement 1(LoadOnDemand), 3, 4, 5, 6, and the performance is still poor on IE, but working better in Firefox.

Loading the data initially is not a problem, but doing a sorting takes for ever in IE.....

Ok a couple of things right out the gate.

1: LoadOnDemand and/or Paging is your Friend.

2: Setting your DataSource at Runtime (when applicable) using a asp:SqlDataSource will save a lot of performance.

3: Set your columns up in the page aspx file not codeBehind
IE: <igtbl:UltraGridColumn Hidden="false" Width="20" BaseColumnName="MyDataField" HeaderText="MyDataText" IsBound="True" Key="MyDataField" />

4: Use the webGrid_InitializeLayout event to setup your fields (ie: hide, center, change caption etc.) that is if you need to do it
dynamicly.

5: Try and prepare your data ahead of time from your storedProcedure (ie: your edit field has <a href etc. in it) so try and just modify
the storedProcedure/Select Statement to just output it for you. If you cannot do that then just use the
webGrid_InitializeRow event to fix the cell like so:
e.Row.Cells(1).Text = "<a href..."

6: Turn off your ViewState The main reason your page is so slow is because it is 1.35 MB and both FF and IE are choking on this across the wire getting script timeouts etc. your viewstate alone is over 500k... if you need your viewstate for some reason (which 90% of the time you don't) then offload it to the server.

All of the above factors play into sorting as well. so until you resolve the "base" issues there is no way it is going to work the way you want it to, for that matter no grid is going to work like that.

BTW Friendly tip hide all the username/password/email information for your test unless "all" of those are test accounts.

Ouch... Why are you looping through all your records?

I just got some feedback from my development team, and the performance problem is occuring only in IE when we use the grouping functionality, sorting, and filtering. The datagrid is working fine in Firefox.

 Actually, sorting 1k rows takes less than 5 secs in Firefox, and more than 1 minute in IE.

 Here is the code used:

       IList<Tech2020.w2020net.Model.User> users;
      
      
       DataTable dt = new DataTable();
      

        CreateColumn(dt, "System.String", "Edit");

        CreateColumn(dt, "System.Int32", "ID");

        CreateColumn(dt, "System.String", "FirstName");

        CreateColumn(dt, "System.String", "LastName");

        CreateColumn(dt, "System.String", "Email");

        CreateColumn(dt, "System.Boolean", "Member");

        CreateColumn(dt, "System.Boolean", "Active");

        CreateColumn(dt, "System.String", "LastLogin");

        CreateColumn(dt, "System.String", "EditedOn");

       
        users = bal.GetUsers(-1); // status 0 == active And 1 == deleted in the ektron system

       
        foreach (Tech2020.w2020net.Model.User user in users)

        {

            DataRow row;

            row = dt.NewRow();

            row["Edit"] = "<a href=\"Edit.aspx?userID=" + user.ID.ToString() + "&KeepThis=true&TB_iframe=true&height=500&width=650&modal=true\" class=\"thickbox\">Edit</a>";

            row["ID"] = user.ID;

            row["FirstName"] = user.FirstName;

            row["LastName"] = user.LastName;

            row["Email"] = user.Email;

            row["Member"] = user.MembershipUser;

            row["Active"] = user.Active;

            row["LastLogin"] = user.DateLastLogin;

            row["EditedOn"] = user.DateModified;

            dt.Rows.Add(row);

        }

        UltraWebGrid1.DataSource = dt;

        UltraWebGrid1.DataBind();