My sd card undetected. How it's happen? And how to fix it

My sd card was vgen and my mobile phone was Lenovo A369i. I have try to reboot and putin-out the sd card but still the same. Anyone know to fix it?

Guest

Try the SD card with something else, like a pc. If it works, then format the sd card (which will wipe everything off of it). If it doesn't work than your sdcard might be bad.

nick