رسالة خطأ عند بدأ البرنامج !

هذه الرسالة :

صوره اخرى :

http://i58.servimg.com/u/f58/17/63/82/27/1-28-211.jpg

هذا الكود في داخل الرسالة :

See the end of this message for details on invoking
just-in-time (JIT) debugging instead of this dialog box.

************** Exception Text **************
System.InvalidCastException: Conversion from type 'DBNull' to type 'String' is not valid.
   at Microsoft.VisualBasic.CompilerServices.Conversions.ToString(Object Value)
   at Store.FrmItems.FillTxt()
   at Store.FrmItems.Move_Last()
   at Store.FrmItems.FrmItems_Load(Object sender, EventArgs e)
   at System.Windows.Forms.Form.OnLoad(EventArgs e)
   at System.Windows.Forms.Form.OnCreateControl()
   at System.Windows.Forms.Control.CreateControl(Boolean fIgnoreVisible)
   at System.Windows.Forms.Control.CreateControl()
   at System.Windows.Forms.Control.WmShowWindow(Message& m)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
   at System.Windows.Forms.ContainerControl.WndProc(Message& m)
   at System.Windows.Forms.Form.WmShowWindow(Message& m)
   at System.Windows.Forms.Form.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)


************** Loaded Assemblies **************
mscorlib
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.3649 (GDR.050727-3600)

----------------------------------------
Management Store
    Assembly Version: 2.6.5.8
    Win32 Version: 2.6.5.8

----------------------------------------
Microsoft.VisualBasic
    Assembly Version: 8.0.0.0
    Win32 Version: 8.0.50727.3053 (netfxsp.050727-3000)

----------------------------------------
System
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.3644 (GDR.050727-3600)

----------------------------------------
System.Windows.Forms
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.3644 (GDR.050727-3600)

----------------------------------------
System.Drawing
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.3644 (GDR.050727-3600)

----------------------------------------
System.Runtime.Remoting
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)

----------------------------------------
Accessibility
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)

----------------------------------------
System.Configuration
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)

----------------------------------------
System.Xml
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.3082 (QFE.050727-3000)

----------------------------------------
System.Data
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)

----------------------------------------
System.Transactions
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)

----------------------------------------
System.EnterpriseServices
    Assembly Version: 2.0.0.0
    Win32 Version: 2.0.50727.3053 (netfxsp.050727-3000)

----------------------------------------

************** JIT Debugging **************
To enable just-in-time (JIT) debugging, the .config file for this
application or computer (machine.config) must have the
jitDebugging value set in the system.windows.forms section.
The application must also be compiled with debugging
enabled.

For example:

<configuration>
    <system.windows.forms jitDebugging="true" />
</configuration>

When JIT debugging is enabled, any unhandled exception
will be sent to the JIT debugger registered on the computer
rather than be handled by this dialog box.
 

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