RECentral shows "Device occupied" error message, how to fix it?
RECentral 4 shows “Device Occupied” error message
If you have already updated your system to Windows 10 
This error is resulted by the new update that controls the way of applications connecting your webcams and video capture devices.
Please refer to following steps to resolve the situation:
In Windows Search type “Privacy Settings” then click “Enter”
1. At Privacy Settings/ App Permissions/ Camera find the toggle and make sure to set it on
“Allow apps to access your camera”
2. At Privacy Settings/ App Permissions/ Microphone find the toggle and make sure to set it on
“Allow apps to access your microphone”
Make sure that your UAC (USB Audio Class) device (for example: GC510, GC513, GC570, BU110) is enabled* at Windows Volume panel under Recording devices.
*Note: if you plug microphone to your system that will be the default device, but UAC device still has to be enabled.
If your device is USB interface (for example: GC510, GC513, BU110) try to remove it from the connected USB port then plug it back.
Reinstall driver for the UAC device: remove the UAC device manually from Device Manager by right click on its name then select “Uninstall device”,
then at Device Manager/Action panel select “Scan for hardware changes”
Go into Windows Task Manager and at Services “Stop” RECentral service
then restart it by clicking “Start” it.
If you set graphic card codec in RECentral 4 settings, make sure to update your standalone graphic card driver to its latest version.