Instructions
Insert your corrupted memory card to your Nintendo GameCube console. Turn on the console by pressing "Power."
Select the "Memory Card Screen" menu option from your Nintendo GameCube's main menu.
Select the "Yes" option when asked whether you would like to format your corrupted Nintendo GameCube memory card.
Select the "Yes" option again to confirm you really would like to format your corrupted Nintendo GameCube memory card. Your Gamecube will format the memory card, and it no longer repeatedly will corrupt itself.