Canon camera says replace card...how do I regain my photos?

Hi friends…

Upon turning my Canon 400D camera on today (yesterday there was no problem) the message displayed on the camera says “there is a problem with the CF card,replace the card” The card is a 4GB Extreme III.My computer will not accept the card either.Please provide me some answers to regain my valuable and amazing photos of my Indian holiday…Thank you,your advise will be treasured…Davey

you will need to send the card for data recovery. here is one company that provides data recovery services. 

http://datarecovery.lc-tech.com/