Capturing Weight Using Scale Interface - 'Run-time error '8005'. Port already open'

Q.  While trying to capture the weight using the Scale Interface, why does the following error message display? 

Run-time error '8005'. Port already open

A.  Check Device Manager for a serial mouse, which will look similar to the following screen shot:

If a serial mouse is listed but not being used, the issue is that the operating system thinks the scale is a serial mouse. Right-click the serial mouse in Device Manager and choose the Disable option.