Complete newbie needs help.....

Hi all.

Hope I've put this post in the right place and I dont wish to offend the more experienced out there but I need some advice.

I have 2 Micro cards, one for each of my 2 boys, to avoid fights you understand....

tonight, all of a sudden, one of the cards stopped working. I have established that it's not the DS or the carts.

When I try to connect the micro SD card to my PC using a usb flash reader I get 'Please insert a disk into drive E:' My PC doesnt seem to recognise that there is a memory card in the usb reader. It reads the other micro SD card fine.

Does this mean that the memory card that wont work is now busted and I need a new one?

If yes, can somebody advise me how this could have happened so I can stop it happening again?

Thanks


Gareth