The driver software may not have been properly installed.
Either change the filename (DDJ-RZX_x.xxx.exe) of the driver software's installer and install again, or check as described below and then reinstall.
1. Disconnect the DDJ-RZX from the USB port.
Do not connect the DDJ-RZX via USB until the driver software is reinstalled.
2. Uninstall the driver software and restart the computer.
3. Right-click the installer file of the driver software and open its properties.
4. Click the "Compatibility" tab and then click "Display the settings of all users".

5. In Compatibility mode, check if the "Run this program in the compatibility mode" check box is selected. If it is selected, deselect the check box and click "OK".
