OS X Yosemite: Check your device’s USB connection
If a USB device isn’t working properly, it might not be properly connected to your computer.
- Check the port and cable connection:If your computer has more than one USB port , switch the device’s cable to another port. If you still can’t use the device, contact the manufacturer for more information.
If you can use the device after switching ports, connect another device to the first port. If you can’t use this device, shut down the computer and unplug it from the power outlet. Wait about a minute, then plug it into the power outlet and start up your computer.
- If the device is connected to a USB hub:Make sure the device and the hub are the same speed. For example, connect a USB 3.0 SuperSpeed storage device to a USB 3.0 SuperSpeed Hub.
- If more than one device is connected to the USB port:Disconnect all other devices. If necessary, connect a keyboard and mouse to another USB port . Do not use USB hubs or extension cords.
If you can use your device now, there may be a problem with one of the other devices. Try reconnecting the other devices, one by one, to your computer. When you find the device causing the problem, check its documentation for further troubleshooting steps.