I’m working on my laptop, and needed to transfer some files. USB keydrive is the easiest way, so I reach around the back and plug it in.

Nothing – doesn’t appear on the USB bus. So I unplug it and try again.

Still nothing – has the USB bus locked up with all the hibernate/restarts I’ve been doing? Unload the driver modules, reload them, all looks good, unplug and plug in again.

Still nothing – dead drive? Plug into another computer, comes up fine.

Take the keydrive back to the laptop, plug it in again. Stop. Think “Isn’t that the wrong side?”. Look at the back of the laptop.

Fun fact: 8C8P (aka ‘RJ45’) connectors are the same width as USB ports…