Corrupted memory cards

Removing cards after writing to them 

It is possible to corrupt the files stored on a memory card by pulling the card out without following the proper procedure. 

When you finish writing to a memory card and wish to remove it you must tell the computer before you remove it. 

If you forget to do this you may end up with a corrupt card - even though it appears to have finished copying files and be doing nothing the computer may not actually have transferred everything to the card. If you pull the card out at this stage the information on the card may be incomplete or damaged. 

To avoid this problem use the Unplug Or Eject Hardware tool - this is the little icon at the bottom right of your screen which looks like a card with a green arrow above it. If you hover your mouse over it it will say "Safely Remove Hardware" (XP) or "Unplug Or Eject Hardware" (Windows 2000).  

Click on the icon and it will pop up a small list of any removable hardware on your machine.  For example, if your memory card was drive G: then you might see a popup message like this: "Safely remove storage device (G:)".  Click on the item you wish to remove (make sure it is the right one!) and after a moment or two it will tell you when it is safe to remove the card.

Other causes

If you are following this procedure correctly and still have problems then it's possible you may have a faulty card or card slot, or the card may have dirty contacts or be badly inserted.  it's also possible that there may be an incompatibility between that particular computer and card type.