Every device I tried plugging into the back have worked [Xbox 360 Controller, Microsoft Digital Media Keyboard, Iomega External Hard Drive, Cannon Digital Camera, Olympus Digital Camera, and an HP PSC 1300 All-in-One].
When I tried plugging devices into the front USB Ports, some of them didn't work. The Xbox 360 Controller was not detected, the Olympus Camera was detected as an Unknown Device, but didn't function. The Cannon Camera and the External Hard Drive worked fine though.
They are all PnP so they don't need drivers, and I have checked that the USB Ribbon Cable and Power Cable are connected correctly inside the PC.
What Should I Do?