Problem: UPS (Uninterruptable Power Supply) is a piece of hardware connected to the serial port, which is supposed to protect the station from power failure. Starting the CPL, the wksvnw.nlm or other WibuKey software, which first scans all ports, results in an error function in the power chute. Reason: This happens because our drivers have general access to the serial port or because the Scan button in the CPL/WkLIST has been pushed. Solution: Disable the port to which the UPS is connected. This can be done in the CPL on page Setup or in the wibukey.ini (wksvnw.nlm, e.g. WkCom=/D,*,*,*, if the power chute is connected to the COM1). In the current driver version the serial interfaces are deactivated as default.