MonoDevelop - illegal character in Path

When ever i try to open a file using MonoDevelop i get this message

System.ArgumentException: Illegal characters in path. at System.IO.Path.GetExtension (System.String path) [0x00000] in :0 at MonoDevelop.Projects.Formats.MSBuild.SlnFileFormat.CanReadFile (System.String file, MonoDevelop.Projects.Formats.MSBuild.MSBuildFileFormat format) [0x00000] in :0 at MonoDevelop.Projects.Formats.MSBuild.MSBuildFileFormat.CanReadFile (FilePath file, System.Type expectedType) [0x00000] in :0 at MonoDevelop.Projects.FileFormatManager.GetFileFormats (System.String fileName, System.Type expectedType) [0x00000] in :0 at MonoDevelop.Projects.ProjectService.IsWorkspaceItemFileInternal (System.String filename) [0x00000] in :0 at MonoDevelop.Projects.DefaultProjectServiceExtension.IsWorkspaceItemFile (System.String filename) [0x00000] in :0 at MonoDevelop.Projects.ProjectServiceExtension.IsWorkspaceItemFile (System.String fileName) [0x00000] in :0 at MonoDevelop.Projects.ProjectServiceExtension.IsWorkspaceItemFile (System.String fileName) [0x00000] in :0 at MonoDevelop.Projects.ProjectServiceExtension.IsWorkspaceItemFile (System.String fileName) [0x00000] in :0 at MonoDevelop.Projects.ProjectServiceExtension.IsWorkspaceItemFile (System.String fileName) [0x00000] in :0 at MonoDevelop.Projects.ProjectServiceExtension.IsWorkspaceItemFile (System.String fileName) [0x00000] in :0 at MonoDevelop.Projects.ProjectServiceExtension.IsWorkspaceItemFile (System.String fileName) [0x00000] in :0 at MonoDevelop.Projects.ProjectServiceExtension.IsWorkspaceItemFile (System.String fileName) [0x00000] in :0 at MonoDevelop.Projects.ProjectServiceExtension.IsWorkspaceItemFile (System.String fileName) [0x00000] in :0 at MonoDevelop.Projects.ProjectService.IsWorkspaceItemFile (System.String filename) [0x00000] in :0 at MonoDevelop.Ide.IdeApp.OpenFiles (IEnumerable`1 files) [0x00000] in :0 at MonoDevelop.Ide.IdeApp+c_AnonStorey8E.<>m_10F (System.Object , System.EventArgs ) [0x00000] in :0 at (wrapper delegate-invoke) :invoke_void_this__object_EventArgs (object,System.EventArgs) at MonoDevelop.Ide.Id开发者_StackOverflow中文版eApp.Initialize (IProgressMonitor monitor) [0x00000] in :0 at MonoDevelop.Ide.IdeStartup.Run (System.String[] args) [0x00000] in :0

Please Advice

This was a P/Invoke marshalling bug in MD 2.4, fixed in 2.4.1.