If you are trying to use a USB port to charge a device, and it is not working, there are tools in Windows that can help. Go to Control Panel -> Device Manager -> and select Devices by Connection from the View menu. Click the name of your PC and press the asterisk (*) key. This will open a list of devices connected to your system. Scroll down till you find “Generic USB Hub”. Right-click that item and select Properties. Then click the Power tab.

After all that clicking, you will see a list of USB devices, and the amount of power that each one is drawing. This information can help you determine whether the device will charge quickly or slowly given the amount of power it is drawing.   Fixing the problem could take a bit of trial and error, but start by unplugging any non-essential USB devices and see if the numbers change.