Sometimes after an Windows update, drivers for cable will crash, then it is unable to connect Zelio relay with PC. To fix this issue, please follow below step and use the picture for reference.
Step 1: Make sure the SR2 USB01 cable is connected to PC. In windows, go to Control Panel and then find Device Manager. Find Ports (COM & LPT) and then find Zelio Serial Port.
Step 2.1: Double click Zelio Serial Port. to open the property window, move to Driver tab, then click Uninstall Device. In the popup window, tick Attempt to remove the driver from this device, then click Uninstall.
Step 2.2: In the Device Manager, find Universal Serial Bus controllers and then find Zelio SR2 USB01 H2.x. double click it to open the property window, move to Driver tab, then click Uninstall Device. In the popup window, tick Attempt to remove the driver from this device, then click Uninstall.
Step 3: Reinstall the driver by using SR2_USB01_H2.x_Setup.exe.