window in EditorWindow

hello

i post one more time the ultimate question :

is it possible to open a window inside a editorwindow with a button ?

i try it with beginwindow endwindow but i have conflict with the other beginvertical beginhorizontal

where is the solution ?

thanks for your help ...

Did you read this reference manual? It's entirely possible:

http://unity3d.com/support/documentation/Components/gui-ExtendingEditor.html

If you're having a specific issue, be specific in your question. We can't help you unless you provide more details, what you provided was too vague. It helps to post code, too.