edmx files error

When i try to open an .emdx file which has been created in VS2012(VB) i got unhandled exception:

SharpDevelop Version : 4.3.0.9338-alpha-5f770be6

.NET Version : 4.0.30319.18034

OS Version : Microsoft Windows NT 6.1.7601 Service Pack 1

Current culture : Arabic (Qatar) (ar-QA)

Current UI language : en

Running under WOW6432, processor architecture: x86-64

Working Set Memory : 106648kb

GC Heap Memory : 27380kb

Exception thrown:

System.NullReferenceException: Object reference not set to an instance of an object.

at ICSharpCode.Data.EDMDesigner.Core.UI.DisplayBinding.EDMDesignerViewContent.Dispose()

at ICSharpCode.SharpDevelop.OpenedFile.ForceInitializeView(IViewContent view)

at ICSharpCode.SharpDevelop.FileServiceOpenedFile.ForceInitializeView(IViewContent view)

at ICSharpCode.Data.EDMDesigner.Core.UI.DisplayBinding.EDMDesignerViewContent..ctor(OpenedFile primaryFile)

at ICSharpCode.Data.EDMDesigner.Core.UI.DisplayBinding.EDMDesignerDisplayBinding.CreateContentForFile(OpenedFile file)

at ICSharpCode.SharpDevelop.FileService.LoadFileWrapper.Invoke(String fileName)

at ICSharpCode.Core.FileUtility.<>c__DisplayClass14.<ObservedLoad>b__13()

at ICSharpCode.Core.FileUtility.ObservedLoad(FileOperationDelegate loadFile, String fileName, String message, FileErrorPolicy policy)

at ICSharpCode.Core.FileUtility.ObservedLoad(NamedFileOperationDelegate saveFileAs, String fileName, String message, FileErrorPolicy policy)

at ICSharpCode.Core.FileUtility.ObservedLoad(NamedFileOperationDelegate saveFileAs, String fileName, FileErrorPolicy policy)

at ICSharpCode.SharpDevelop.FileService.OpenFile(String fileName, Boolean switchToOpenedView)

at ICSharpCode.SharpDevelop.Project.FileNode.ActivateItem()

at ICSharpCode.SharpDevelop.Gui.ExtTreeView.OnMouseDoubleClick(MouseEventArgs e)

at System.Windows.Forms.TreeView.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)

---- Recent log messages:

13:54:37.130 [LoadSolutionProjects] DEBUG - RefreshProjectContentForReference: not refreshing (rpc.IsUpToDate) C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.5\System.Xml.dll

13:54:37.130 [LoadSolutionProjects] DEBUG - Loading PC for System.Xml.Linq

13:54:37.130 [LoadSolutionProjects] DEBUG - Try find XMLDoc @C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.5\en\System.Xml.Linq.xml

13:54:37.130 [LoadSolutionProjects] DEBUG - Try find XMLDoc @C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.5\System.Xml.Linq.xml

13:54:37.130 [LoadSolutionProjects] DEBUG - Loading XmlDoc for C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.5\System.Xml.Linq.xml

13:54:37.150 [8] DEBUG - Adding existing class MyApplication from Application.Designer.vb

13:54:37.150 [8] DEBUG - Creating compound for WindowsApplication1.My.MyApplication

13:54:37.150 [1] DEBUG - ParseInformationUpdated C:\Users\Eiad Al-Khanshour\Documents\Visual Studio 2012\Projects\EntityDataTest\WindowsApplication1\Form1.vb new!=null:True

13:54:37.150 [1] DEBUG - ParseInformationUpdated C:\Users\Eiad Al-Khanshour\Documents\Visual Studio 2012\Projects\EntityDataTest\WindowsApplication1\My Project\Application.Designer.vb new!=null:True

13:54:37.150 [1] DEBUG - ParseInformationUpdated C:\Users\Eiad Al-Khanshour\Documents\Visual Studio 2012\Projects\EntityDataTest\WindowsApplication1\My Project\AssemblyInfo.vb new!=null:True

13:54:37.160 [1] DEBUG - ParseInformationUpdated C:\Users\Eiad Al-Khanshour\Documents\Visual Studio 2012\Projects\EntityDataTest\WindowsApplication1\My Project\Settings.Designer.vb new!=null:True

13:54:37.160 [13] DEBUG - Adding existing class Form1 from Form1.Designer.vb

13:54:37.160 [13] DEBUG - Creating compound for WindowsApplication1.Form1

13:54:37.160 [1] DEBUG - ParseInformationUpdated C:\Users\Eiad Al-Khanshour\Documents\Visual Studio 2012\Projects\EntityDataTest\WindowsApplication1\Form1.Designer.vb new!=null:True

13:54:37.160 [1] DEBUG - ParseInformationUpdated C:\Users\Eiad Al-Khanshour\Documents\Visual Studio 2012\Projects\EntityDataTest\WindowsApplication1\My Project\Resources.Designer.vb new!=null:True

13:54:37.160 [1] DEBUG - ParseInformationUpdated C:\Users\Eiad Al-Khanshour\Documents\Visual Studio 2012\Projects\EntityDataTest\WindowsApplication1\Model1.Designer.vb new!=null:True

13:54:37.160 [1] DEBUG - NavigationService -- resume logging

13:54:37.295 [5] DEBUG - Git: OverlayIconManager Thread finished

13:54:39.613 [1] DEBUG - ActiveContentChanged to ICSharpCode.SharpDevelop.Project.ProjectBrowserPad

13:54:39.613 [1] DEBUG - ActiveWorkbenchWindowChanged to

13:54:39.615 [1] INFO - CurrentProject changed to WindowsApplication1

13:54:39.658 [1] INFO - Loading addin ASP.NET MVC Binding

13:54:39.884 [1] INFO - Open file C:\Users\Eiad Al-Khanshour\Documents\Visual Studio 2012\Projects\EntityDataTest\WindowsApplication1\Model1.edmx

13:54:39.933 [1] ERROR - ThreadException caught

--> Exception: