Do you have a spare desktop pc to put it into?
Make sure your enclosure is a powered one. If it only has one USB cable and no power adapter it isn't going to work with a desktop 3.5in hdd.
Make sure the USB cable is plugged into a USB3 port.
I ended up getting the "Sabrent USB 3.0 TO SATA/IDE 2.5/3.5/5.25-INCH Hard Drive Converter With Power Supply & LED Activity Lights". Got the hard drive to spin, lights are on but nothing is showing up on my laptop. Any ideas? Maybe has something to do with the jumpers?