What does the yellow ! icon against a port mean?

Device: AnywhereUSB /5
Windows 2003R2

The view utility correctly displays details of the dongle plugged into the port in the right hand side. However the port is listed on the left hand side of the view utility with the yellow ! against the port and there is no label on the port. Another port is working and is displayed with the red connection icon. What is the problem with that port?

It sounds like the problematic dongle s recognized by the computer, but maybe the driver isn’t installed. Do you see the problematic in Windows Device Manager? Does it have a yellow warning icon there too?