Crystal Reports login not working in production

See more:

SQL-server-2000

C#

SQL-Server

, +

Firstly, I have this working in development, however when I publish to the production webserver, instead of generating the report, it asks me for login credentials again.
Here is a snapshot of my entire code behind file:

public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if ((ViewState["ParametersShown"] != null) &&
(ViewState["ParametersShown"].ToString() == "True"))
{
ReportListing myListing = new ReportListing();
BindReport(ConfigurationManager.AppSettings["reportlocation"].ToString() + 
myListing.GetReportFileName(Session["Report"].ToString()));
}
}

protected void btnBuild_Click(object sender, EventArgs e)
{
CrystalReportViewer1.ParameterFieldInfo.Clear();
DateTime startDate = DateTime.Parse(Session["FromDate"].ToString());
DateTime endDate = DateTime.Parse(Session["ToDate"].ToString());

ParameterFields paramFields = new ParameterFields();
ParameterField crStartDate = new ParameterField();
ParameterField crEndDate = new ParameterField();
crStartDate.Name = "@StartDate";
crEndDate.Name = "@EndDate";
ParameterDiscreteValue dcrStartDate = new ParameterDiscreteValue();
ParameterDiscreteValue dcrEndDate = new ParameterDiscreteValue();
dcrStartDate.Value = startDate;
dcrEndDate.Value = endDate;
crStartDate.CurrentValues.Add(dcrStartDate);
crEndDate.CurrentValues.Add(dcrEndDate);
paramFields.Add(crStartDate);
paramFields.Add(crEndDate);

ReportListing myListing = new ReportListing();
BindReport(ConfigurationManager.AppSettings["reportlocation"].ToString() + 
myListing.GetReportFileName(Session["Report"].ToString()));
CrystalReportViewer1.ParameterFieldInfo = paramFields;
ViewState["ParametersShown"] = "True";
ViewState["ReportName"] = Session["Report"].ToString();
}
private void BindReport(string FilePath)
{
ReportDocument Report = new ReportDocument();
Report.Load(FilePath);
SetTableLocation(Report.Database.Tables);
CrystalReportViewer1.ReportSource = Report;
}
private void SetTableLocation(Tables tables)
{
ConnectionInfo connectionInfo = new ConnectionInfo();
connectionInfo.ServerName = ConfigurationManager.AppSettings["ReportDBServerName"].ToString();
connectionInfo.DatabaseName = ConfigurationManager.AppSettings["ReportDBDBName"].ToString();
connectionInfo.UserID = ConfigurationManager.AppSettings["ReportDBUserID"].ToString();
connectionInfo.Password = ConfigurationManager.AppSettings["ReportDBPassword"].ToString();
foreach (CrystalDecisions.CrystalReports.Engine.Table table in tables)
{
TableLogOnInfo tableLogOnInfo = table.LogOnInfo;
tableLogOnInfo.ConnectionInfo = connectionInfo;
table.ApplyLogOnInfo(tableLogOnInfo);
}
}
}

As detailed above, running from a local machine it works fine. It is only when published to production server it asks for login details. Login details are stored in the web.config file and are correct.
Please help!
Thanks

[Moved from Answers]

Yes, Anonymous access is enabled and it has suitable permissions on the folder. The credentials it is asking for is the database credentials. When working on development server it was pointing at the same database, but since publishing to production, it asks for database login credentials. Also (rather weirdly), it won't let me type in database name when asked for the credentials either.
If I run exactly the same application from my development machine it correctly passes the DB parameters and login info, thus bypassing the DB login screen correctly. I can see no legitimate reasoning for this behavior.

Solution

I have resolved this. Problem is that it uses the SQL Native Client, which is not installed on the production server. I have since installed this and all is working.