I recue with 10 jous delay, the startup has posed problems (Windows 7) I can not reuse the port from the previous mouse so you have to assign a new port, I had to try several ( hubx4) and finally arrived. Otherwise it is a beautiful object which fonctione perfectly, two-speed 800 and 1600dpi handgrip: retro annoy some right même.Dommage. Regards, Eric