nRF52840 Preview DK not appear as a removable drive.

Dear all,

I was following the "Getting started with the nRF52840 Preview Development Kit" page. But when i connect the board to the computer, the board do not appear as a removable drive, the LED1 is on, and using the buttons SW1 to SW4 i can control which led is on. I have a Windows 10 Pro 64bits, processor based on x64. Is necessary to install some driver?

Any help will be very appreciatted. Best regards, Rafael Costa