X220 : No device connected but error message keeps popping up

[#1]

Question

My X220 does not have a device connected to any of its three USB ports, but I get this error message:

"One of the USB devices attached to this computer has malfunctioned and Windows does not recognize it."

In the Device Manager I see that there is an Unknown Device detected, but when I checked the properties of this device the error message "Currently, this hardware device is not connected to the Computer - Code 45).

Answer

Your system could have had some water damage. 

USB ports are sensitive to moisture and humidity, and users are advised not to use their systems in conditions where humidity exceeds 95%.