Lost data from SD card - help!

[ilesmark]

Hi all

I have a Canon 550D. While I was in Tanzania recently, I filled one of the SD cards up with videos and pics and went to an internet cafe intending to get the data off the card and onto a DVD. Bad move. When I tried to do this, it told me the DVD had burned but then there was no sign of any data on the DVD. I did not delete the data from the card, only copied it. When I put the card back in the camera and tried to take a picture, it said 'unable to create folder' (or words to that effect) and then said 'no image' when I tried viewing any of the pics.

I did nothing more with that card after that until I got home yesterday and put it in my home PC. I opened it in Windows Explorer and momentarily saw the usual DCIM and MISC folders, then immediately the McAfee Anti Virus software told me it had intercepted 2 viruses on the card. Now, viewing it in Windows Explorer, I can see no data on the card and neither can I see the DCIM or MISC folders. BUT when I right click on properties, it tells me the card remains full almost to capacity.

How can I get the pics/videos back?

Thanks

Mark