Nikon D5100 not recognized by mac or PC?

A little over a year ago, I bought myself a brand new $1, 100 camera and it was fantastic! Everything worked, I was able to connect it to my computers no problem. Then, today I try and plug it into my mac computer to load pictures as usual, and it isn't recognized. I also tried plugging it into my newer PC and a brand new mac both with no luck. I have already looked and there are no USB settings on my camera to change, so it's not the MTP/Mass storage. I also do not have the ability to get an SD card reader at the moment. Is there anything I could do to FIX this?

Follow the instructions in your user manual to the letter.

As soon as you can buy a USB card reader. I'm surprised that neither of your computer do not have a card reader.

Those of us who have been shooting digital cameras long ago stopped using our cameras USB ports to copy images to our computers and instead, use a USB 2.0 reader. Some of us with newer cameras use USB 3.0 card readers.

You may need a software update for your camera. I tried connecting my camera to the computer and low and behold an update was given. The update was for the newer memory cards verses the ones sold oh, about a years ago. I would try this first and then go from there.

I hardly ever plug my camera into the USB. I once had a problem with a PC where the fault caused over-voltage to the USB port that blew the HDD I had plugged in.

Use a USB card reader. Better to sacrifice a £10 USB card reader than a £500 camera!

As others have said, use a USB SD card reader. They aren't expensive or hard to come by:

UK: http://www.amazon.co.uk/...000VY80AM/

USA: http://www.amazon.com/...001NS828K/

It doesn't have to be recognized as a camera. If you're just going to transfer files, your very expensive camera will only act as a USB card reader for the computer. It really is best to take the camera out of the way. Use a cheap USB card reader to connect your camera's memory card directly to the computer to eliminate all camera to computer connection problems. Use Windows Explorer or (Mac) Finder to do the actual transfers for absolute total control over what goes where exactly.