Steps to reproduce the behavior

1. Start Visual Studio .NET.
2. On the File menu, point to New, and then click Project.
3. Click Visual Basic Projects under Project Types, and then click Windows Application under Templates.
4. Name the project MySqlApplication, and then click OK.
5. In the Code View window of Form1, replace the existing code with the following code:

   Public Class Form1
       Inherits System.Windows.Forms.Form
   
   #Region " Windows Form Designer generated code "
   
       Public Sub New()
           MyBase.New()
   
           'This call is required by the Windows Form Designer.
           InitializeComponent()
   
           'Add any initialization after the InitializeComponent() call
   
       End Sub
   
       'Form overrides dispose to clean up the component list.
       Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
           If disposing Then
               If Not (components Is Nothing) Then
                   components.Dispose()
               End If
           End If
           MyBase.Dispose(disposing)
       End Sub
   
       'Required by the Windows Form Designer
       Private components As System.ComponentModel.IContainer
   
       'NOTE: The following procedure is required by the Windows Form Designer
       'It can be modified using the Windows Form Designer.  
       'Do not modify it using the code editor.
       Friend WithEvents Timer1 As System.Windows.Forms.Timer
       <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
           Me.components = New System.ComponentModel.Container()
           Me.Timer1 = New System.Windows.Forms.Timer(Me.components)
           '
           'Timer1
           '
           Me.Timer1.Enabled = True
           Me.Timer1.Interval = 500
           '
           'Form1
           '
           Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
           Me.ClientSize = New System.Drawing.Size(292, 266)
           Me.Name = "Form1"
           Me.Text = "Form1"
   
       End Sub
   
   #End Region
       Public Sub CreateSqlConnection()
           Dim myConnection As New SqlClient.SqlConnection()
   							
   							'replace the connection string with the your connection string to SQL Server
           myConnection.ConnectionString = "Data Source=myserver;Integrated Security=SSPI;Initial Catalog=northwind"
           
           ' Opens a database connection with the property settings specified by the ConnectionString.
           myConnection.Open()
         
          ' Closes the connection to the database.
           myConnection.Close()
       End Sub
   
       Private Sub Timer1_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles Timer1.Tick
           Timer1.Enabled = False
           CreateSqlConnection()
       End Sub
   End Class
   

6. Add a breakpoint at CreateSqlConnection in the Timer1_Tick event procedure.
7. Press F5 to debug the project. Program execution breaks at breakpoint.
8. Press F11 to step into the CreateSqlConnection event procedure.
9. Press F10 until you reach myConnection.Open().
10. Press F10. You receive the error message that is mentioned in the "Symptoms" section.

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