A VB6 user control can include one or more properties that are available only at runtime and that shouldn’t appear in the property window. By convention, such a property should raise error 382 or 387 in the Property Get procedure, as in:
Property Get hWnd() As Long
If Not Ambient.UserMode Then Err.Raise 382
During the conversion to VB.NET, such properties should be marked with the Browsable(False) attribute to hide them in the property window, and with the DesignSerializationVisibility(DesignerSerializationVisibility.Hidden) attribute to avoid persistence in the designer. VB Migration Partner correctly detects this situation and generates these attributes as needed.