My card reader is being recognized by my machine, but the memory card is not.

Sometimes, if the card reader is inserted without a memory card in it, the computer will recognize the drive, but not refresh itself when a card is inserted. The simple fix is to insert the memory card into the card reader before it is inserted into the laptop. Rebooting the computer with the memory card in it should have the same effect as well. Please be aware that the card may take up to a minute to mount on your computer.