Go to Tools - VSdocman menu or press VSdocman button on standard toolbar. VSdocman dialog appears, select Project Properties pane. Set Miscellanous - Root Namespace page.
This section only applies to Visual Basic because C# doesn't have concept of a root namespace. Because root namespace has no source code representation, this dialog is the only place where you can define a comment for the root namespace.
Root namespace comment
This is an XML comment (without comment prefix /// or ''') of the root namespace as it would appear in source code.