Devices such as external hard drives and flash drives require USB ports to transfer data with a computer. You can use the Device Manager in Windows 7 to monitor USB ports as well as USB devices attached to your computer. If your computer cannot detect a USB device, try refreshing the USB port that you attached the device to by using the Device Manager.
Step 1
Click the "Start" button, type "devmgmt.msc" without quotes and press the "Enter" button.
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Step 2
Expand the option labeled "Universal Serial Bus Controllers" by double-clicking it.
Step 3
Right-click a USB port and click the "Properties" option.
Step 4
Click the tab labeled "Advanced."
Step 5
Click the button labeled "Refresh" to refresh the USB port.
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