An exception occurred loading the design canvas: Object refe

my old enemy is back !

oe 11.1 , windows (obviously)

this is the code, created simply by file->new->abl form

 /*------------------------------------------------------------------------
    File        : foo
    Purpose     : 
    Syntax      : 
    Description : 
    Author(s)   : jmls
    Created     : Wed Dec 19 12:24:59 GMT 2012
    Notes       : 
  ----------------------------------------------------------------------*/
using Progress.Lang.*.
using Progress.Windows.Form.
class temp.foo inherits Form: 
     
     define private variable components as System.ComponentModel.IContainer no-undo.
          
     constructor public foo (  ):
               
    super().
    InitializeComponent().
    this-object:ComponentsCollection:ADD(this-object:components).
    catch e as Progress.Lang.Error:
      undo, throw e.
    end catch.
     end constructor.
     method private void InitializeComponent(  ):
          
    /* NOTE: The following method is automatically generated.
    We strongly suggest that the contents of this method only be modified using the
    Visual Designer to avoid any incompatible modifications.
    Modifying the contents of this method using a code editor will invalidate any support for this file. */
    this-object:SuspendLayout().
    this-object:Name = "foo".
    this-object:Text = "foo".
    this-object:ResumeLayout(false).
    catch e as Progress.Lang.Error:
      undo, throw e.
    end catch.
     end method.
     destructor public foo ( ):
     end destructor.
end class.

try to view-.>design, and the error occurs.

How can I fix this ?

Julian