Is another Windows application blocking FlukeView Forms from using this COM port?
If another Windows program is currently using the selected serial port on the PC, FlukeView Forms will be unable to communicate with the meter. For example, the Palm Pilot Hotsync Manager is often left monitoring the COM port used by the Palm Pilot’s cradle. If the cradle is disconnected from the COM port and the IR/serial cable connected in it’s place, but the Hotsync Manager software is not switched off, the Hotsync Manager will continue to block use of the serial port.