Yes , quite simple. Worms and autorun malware hide themselves and mess with file extensions.
Burn a linux live boot cd ,like ubuntu, Insert the cd, turn off the machine, insert the memory card and reboot. The machine should boot from the cd ( if not, you need to alter the boot sequence to cd.dvd first )
While booting from linux, explore the memory card. Now either copy your files to C drive, or simply delete the virus and autorun.inf file.
If your memory card is infected, chances are your pc is too. Unless you clean the pc, the infection cycle will continue