Scrolling problem in ADE 4.0.3

Hello,

I'm trying to use ADE 4.0.3 under Windows 7 pro with a Dell E6530. When I upload a epub into the ADE-library and after double-clicking on the book, it loads and ADE shows the first page. But, when I try to "turn" from a page to the next one, using the scroll bar, the scroll arrow, the menu "next" or the "go to" menu, the page didn't jumped to the next one. The view remains on the first page. If I maximize or minimize the ADE window, the good page appears.

How can I solve this problem ?

Thanks for th help.

GS