Q: when using a usb printer cord, how can you tell which com number the device is on the bus???
A: USB devices don't use COM #'s. COM's are used for the serial interfaces, i.e. com1, com2, etc... USB devices will usually automatically be identified and attached to the computer when they are plugged in. If you're trying to setup a printer using USB and it doesn't automatically get recognized and setup, then you'll have to go into the Printers and Faxes section and manually install the printer to an empty USB port name in the available port listing. It may have a name such as DOT or USB. I've included a link below that may be of help to you as well. Best of luck.