Resolved superdrive usb enclosure

Hi all. I've just upgraded my late 2011 macbook pro (2.4 i5) to SSD fitted using an adaptor in the optical bay and it works superb, hitting 330mb write, 510mb read speeds and its running real smooth.

Since I removed the superdrive I ordered a usb enclosure from an eBay seller who has sold 1000+ of these and when I've received it I can not get it to work.

I plug the drive in to the enclosure and plug it in to my mac and nothing. No noise, no response on mac, nothing. I suspect its a faulty unit and the seller has offered to refund me in full on returning the unit.

Before I ship it back is this anything stupid I could be missing? I've plugged the drive in to the bay, plugged the usb in to the macbook pro (and an air) and nothing happens.

Thanks

will any external cd/dvd drive work with yosemite? I don't mind what route I take but it would be useful to have an external drive for occasional use.

it seems i've managed to get it working. I don't really know what I did differently but its working just fine now. happy days! I thought I would give it one last try before posting it back to the supplier and it worked. weird.