So either the LED's are all blown, or the controller is fried.

That's why you need a meter to do any decisive troubleshooting as suggested in post #8. Most likely you blew the controller.
SG

 

But there’s a MAJOR difference in your test.

Motors spinning is not polarity sensitive (excluding direction). They’ll spin no matter how you connect the wires. Just in different directions.

The LED strip and controller IS polarity sensitive. If connected backwards, the least that will happen is they won’t light. At most, you can blow them or the controller.

The USB lead is wired correctly since I soldered it back exactly where it was before when it was working. The chances of the LED strip having blown is extremely unlikely since it was left unused for over a year and only stopped working when I plugged it back into a USB port before any re-soldering. Though whether it was a 2.0 port or 3.0 I can't recall. Shouldn't matter though.

 

Excuse my persistence, but how are you certain it was soldered back “exactly as it was before”? When you removed it, did you mark the original position in any way? Were there marks on the controller that indicated wire position?

I’m not picking on you. I have made many mistakes similar to this in the past. Most experts here have as well. It’s a common and easy mistake.

And it explains your symptoms. “If it looks like a duck, walks like a duck and quacks like s duck...” and so on.

I’m just trying to rule out an obvious solution. Occam’s Razor and do on. So humor us.

 

Excuse my persistence, but how are you certain it was soldered back “exactly as it was before”? When you removed it, did you mark the original position in any way? Were there marks on the controller that indicated wire position?

I’m not picking on you. I have made many mistakes similar to this in the past. Most experts here have as well. It’s a common and easy mistake.

And it explains your symptoms. “If it looks like a duck, walks like a duck and quacks like s duck...” and so on.

I’m just trying to rule out an obvious solution. Occam’s Razor and do on. So humor us.

This is why I'm asking for a picture of the soldered connections and the circuitry of the board.

I suppose if I made that mistake (and I've made mistakes like this as well) I would probably go on insisting I did it right. Even if I discovered I did it wrong. But that's me. I'm not suggesting @soopytwist is misleading us out of embarrassment, I'm just saying that this is what I might do. Insist it still is not working even though it's correctly wired. BESIDES - who's to say he didn't solder it backwards at one time and blow the thing out then wire it correctly hoping to make it work. I've run across all kinds of people who do all kinds of things for all kinds of reasons. Soopy - please post pictures. That way you can prove me wrong.