How are you plugging it in? Via the USB adapter or SD adapter.
What do you mean not reading it? You plug it in and nothing comes up, or you plug it in you see it in my computer but when you click it nothing comes up or it doesn't come up?
Put it into a mobile phone or anther device and see if the device can read it then try format it.
What SD card as it? How old is it? Is your mother good looking?
Come on man, please next time post more details and try troubleshooting, the more details and troubleshooting you post, the better information your going to get from us. Any maybe next time people wont just skip you topic.