Instructions
Insert the memory card into the second card slot on the right hand side of the PS2. Take any game disc out of the PS2 and then turn the machine on. Select the memory card from the browser. If you are able to see your saved games it may be an issue with card slot 1.
Try to clean out card slot 1. Blow a small amount of air into the area to remove any dust from the card slot. Try the card back in the card slot. Turn on the game and check the browser to see if you can see your saved games.
Try a different game on the PS2. If one game is not able to save on the memory card, there may be an issue with the game itself and not the card.
Test the memory card in a different PS2. If a different PS2 is able to read and write on your memory card, it may be the PS2 that is malfunctioning. Take the system to a reputable game repair shop.
Delete any corrupt files found on a memory card. When viewing saved games on the memory card, there will be files that will display as corrupted. Select these files and chose the delete option. These files may take many attempts to remove this data. In worst-case scenarios, the file will not delete.