You probably need to format it while installed in the camera.
To transfer photos from your Canon camera to your computer, you can use a USB cable to connect the camera to the computer. Once connected, your computer should recognize the camera as a storage device, allowing you to access and transfer the photos to your computer's storage. Alternatively, you can also remove the memory card from the camera and insert it into a card reader on your computer to transfer the photos.
The camera doesn't recognize the card. Take the 10 yardpenalty and punt!
take your memory card out of your camera and there should be a place for it in your computer
Normally you should be able to reformat the card in your camera. If the camera does not recognize the card at all when the card is plugged in, then something else is wrong. The below listed related link outlines several freeware software for recovering accidentally deleted pictures. One of these from VAIOSoft includes several other options for restoring and reformatting your card. Recommend giving it a try to see if it will jog your card back into a recognizable format.
Three ways to read photos from a camera. ( 1)Take the card out of the camera and put it a card reader on the computer or (2) hook up the camera via USB to the computer and the computer will connect to the camera. You have to make sure the camera is on. (3) Finally,you can take the card to a photo center and they can read it and print photos.
USB cable connecting camera to computer or take out SD card and put it in SD card reader on computer
You can get a cable for your camera which would connect to a computer USB port.
To transfer photos from your Nikon D3300 to your Mac, you can use a USB cable to connect the camera to your computer. Once connected, your Mac should recognize the camera as a storage device, allowing you to access and transfer the photos to your computer. Alternatively, you can also remove the memory card from the camera and insert it into a card reader on your Mac to transfer the photos.
You will have to look at the manufactureres specifications for your card.
To transfer pictures from your DSLR camera to your computer, you can use a USB cable to connect the camera to the computer. Once connected, you can access the camera's storage and copy the pictures to your computer's hard drive. Alternatively, you can remove the memory card from the camera and insert it into a card reader connected to your computer to transfer the pictures.
It's possible that the card is faulty; but a simple thing you might be able to try is using a different computer or plugging the card into a camera and then connecting the camera to the computer to see if you can read it that way.
The best way to transfer video footage from a video camera to an SD card is to connect the camera to a computer using a USB cable, then copy the video files from the camera to the computer, and finally transfer the files from the computer to the SD card.