Leonardo - serial port greyed out

For the love of god, can someone please help me, I've wasted a whole day on this.

I simply want to connect to my Leonardo on Windows 7, but the 'serial port' is greyed out.

Other instructions have stated to go to device manager and select either 'Ports' or 'Other Devices' and right click on the Leonardo to update drivers, but neither of these items show up on my list.

The Leonardo itself shows up in the IDE, but not an option for serial ports.

It seems like I have to install a driver for the Leonardo, but the only instuctions I find tell me to do the above, which is not possible.

Please help!

SOLVED: Usb cable was powering the device but not making a data connection. Grrrrr!