First, right-click on the Computer icon, select Manage and open Device Manager. Expand the Universal Serial Bus controllers list, right-click on the driver and select Uninstall. Reboot your PC, connect the ICD-P520 recorder using the USB cable and press Scan for hardware changes icon from Device Manager. Windows will automatically find and install the drivers. If it is still not recognized, uninstall Sony Digital Voice Editor, run CCleaner to make sure that there are no leftover rogue registry keys in your system and download and install the latest version of the software. If you still have issues, I suggest you to contact the Support Team.