Thanks Fabio.
what code you point ?
i corrected the code for Koen in Message ID:1629571 (added h file and 2 scrolls buttons for test).
Yes VFP have not implemented the scrollable container even if it builds all its windows as scrollable !
i guess vfp used the createWindow API to build all its windows and controls,....
the VFP form is a great container when scrollbars=2 (vertical scroll) or 3 (both H+V) but it seem to me its limited in capacity(memory).
can see 2 prg's solutions of vfp scrolables class in:
http://yousfi.over-blog.com/2016/01/the-vfpscrollbar-container-class-as-prg-code.html
-as you see in the Kyrov class there is any documentation and its difficult to traverse the puzzle...

note that in the Koen example,when scrolling with the 2buttons the scrollbar is not update its position.....