My memory card data has been corrupted, all of it. What do I do?

Chances are most likely you have to restart the game. Try taking it in and out though, very rarely it does that when it is not in quite all the way. What type of memory card are you using? (As in Nintendo, Madcatz, Nyto, ETC)

Try blowing into it. That happened to me but I managed to save it.

I don't know if its just me, but my memory card has been corrupted a good 7 or 8 times, and every time I fixed it by just blowing into it.

I've tried blowing into it, but it hasn't worked. and my memory card is by Nintendo.

That's very weird... Did you quit while saving? That's normally it. If you did, you have to restart, if not, keep on blowing into the card over and over and then reinsert it. It should work. If it doesn't, I am afraid you may have to restart.

Try blowing into the actual port where the card goes.

I don't understand. It says that I have to format it, but it won't let me. Would it work in an actual GCN or is it just the Wii?