Can't access camera memory card

[Michael Satterwhite]

I have a usb card reader for my camera's memory card. I've been using it 
without any problems, but when I went to use it today, it's not working; it 
doesn't recognize that I've put a card into it.

My first inclination was to reboot to see if I had a service that wasn't 
running, but that didn't do anything for me.

Can anyone offer any help here?