Thank you for this quick response.
does explorer crash if you log in as a different user?
=> I can't create new accounts on my computer. I'm admin on my computer, but we're in a network whit Active Directory, and i can't create an acocunt on my computer without relying it with an Active Directory Account.
are you using any other desktop enhancement tools?
=> Just Ultra Monitor, for dual monitor display.
are you using any plugins (toolbars, etc) for Internet Explorer?
=> Developper Tooles
do you have the latest hotfixes for Windows 7?
=> Windows Update shiled is "green" ^^ (i don't know how to explain this in good english). But it says there's 4 facultatives updates avalaible. I'll try to install it.
[Edit] => I installed all hotfixes for Windows 7 and file explorer still crashes after 5 to 10 minutes.