The signal coming directly from the seismometer is quite weak and requires amplification in order to see activity. It also requires conversion form an analog to digital signal. With the help of Martin Smith and Chris Knudsen, we have created the NERdaq: an amplifier, filter and Analog-to-Digital signal converter in one! For it to work, you need to install the drivers to the arduino uno board that is at the heart of the NERdaq. Once the Arduino is loaded, there is no need to open or launch it.
If you unplug the USB cable, and plug back in, it may be that your computer sees this as a NEW device. If that is the case, windows will pop up a messsage to (re)install the driver. Follow section 4 of this link: drivers, and check for the new com port in the device manager.