The ConnectionString property has not been initialized with OleDB connection

Question

I have a legacy application that I am migrating off an old server onto a new one. The application is written in VB and I am simply forklifting it from one server to another. The application works fine in it's current location and the only change I made when I moved it was to update the connection strings to reflect the new database. For some reason, I now get the following error only on the OleDB connection string based on the stack trace. The other difference here is that the application on the new server uses domain accounts to authenticate the DB and not SQL accounts.

So, 1. Can you use domain accounts with an OleDB connection? 2. Is there another cause for this error?

Thanks in advance!

Connection String:

     <add key="ConnectionString" value="SERVER=SQLDEV1\SQLDEV1;DATABASE=Comp_Dev;Integrated Security=SSPI;" />
     <add key="SQLConnectionString" value="Provider=SQLOLEDB;Data Source=SQLDEV1\SQLDEV1;Initial Catalog=Comp_Dev;Integrated Security=SSPI;" /> 

Decompiled Code:

private void DisplayManagers()
    {
      this.wkSQL = " SELECT lngManagerID, strName FROM Managers order by strName ";
      OleDbConnection oleDbConnection1 = new OleDbConnection(Conversions.ToString(this.Session["database"]));
      oleDbConnection1.Open();
      OleDbDataReader oleDbDataReader1 = new OleDbCommand()
      {
        Connection = oleDbConnection1,
        CommandText = this.wkSQL,
        CommandType = CommandType.Text
      }.ExecuteReader(CommandBehavior.CloseConnection);
      this.Manager1.DataValueField = "lngManagerID";
      this.Manager1.DataTextField = "strName";
      this.Manager1.DataSource = (object) oleDbDataReader1;
      this.Manager1.DataBind();
      this.Manager1.Items.Insert(0, new ListItem());
      this.wkSQL = " SELECT lngManagerID, strName FROM Managers order by strName ";
      OleDbConnection oleDbConnection2 = new OleDbConnection(Conversions.ToString(this.Session["database"]));
      oleDbConnection2.Open();
      OleDbDataReader oleDbDataReader2 = new OleDbCommand()
      {
        Connection = oleDbConnection2,
        CommandText = this.wkSQL,
        CommandType = CommandType.Text
      }.ExecuteReader(CommandBehavior.CloseConnection);
      this.Manager2.DataValueField = "lngManagerID";
      this.Manager2.DataTextField = "strName";
      this.Manager2.DataSource = (object) oleDbDataReader2;
      this.Manager2.DataBind();
      this.Manager2.Items.Insert(0, new ListItem());
    }

Error:

Server Error in '/LicenseCompliance' Application.
--------------------------------------------------------------------------------

The ConnectionString property has not been initialized. 
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.InvalidOperationException: The ConnectionString property has not been initialized.

Source Error: 

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.  

Stack Trace: 


[InvalidOperationException: The ConnectionString property has not been initialized.]
   System.Data.OleDb.OleDbConnection.PermissionDemand() +1674465
   System.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource`1 retry, DbConnectionOptions userOptions) +6600667
   System.Data.ProviderBase.DbConnectionInternal.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +27
   System.Data.OleDb.OleDbConnection.Open() +47
   LicenseCompliance.search.DisplayManagers() in C:\Users\12876\Documents\Visual Studio 2010\Projects\LicenseCompliance\search.aspx.vb:47
   LicenseCompliance.search.Page_Load(Object sender, EventArgs e) in C:\Users\12876\Documents\Visual Studio 2010\Projects\LicenseCompliance\search.aspx.vb:34
   System.Web.UI.Control.LoadRecursive() +71
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3178

Answer 1

the connectionString you have kept in config file does not belong to OleDB, rather it is of SQL Server. Please check it to be like of OLEDB

Or else you may try by avoiding Oledb in your application and convet it to SQL try by this

imports System.Sql.SqlClient

and then replace all OldDb with SQL, e.g. OleDbCommand to SqlComamnd

Answer 2

You need to reference the connection string like so:

System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString