R4 (please please help!)

have recently bought the R4 for my ds lite and all was working fine. i now but the memory card into the card reader for the pc to add on more files and the pc picks up the flash drive, goes into autoplay (although doesnt show any files loading) and then...nothing.I try and explore the drive but it says i need to format. so i have tried this but windows says it is unable to format the card! now the card itself still works in the ds fine and i can still access the files on there, but i am unable to add more...please help!

try replacing the memory card or the reader

EXACTLY the same thing that happened to me.
it's dead. live with it. or you could try running a chkdsk program.

ahh was the reader...simples!!cheers though guys