Make sure you set the programming software to use the proper COM port that the cable is currently assigned to. When you use a USB programming cable, the driver sets up a virtual COM port in Windows. The Icom software then needs to know which to use.
To find out which COM port the cable is currently assigned to, go to "Control Panel", open "System", click the "Hardware" tab, then click "Device Manager". With the cable plugged in, you should see "Ports (COM & LPT)" in the list. Under that heading, there should be a COM port for your cable.