USB virus all files turning to shortcuts!?

So at school this guy gave me a USB to copy some files over to my computer and I couldn't copy them because the file was somehow turned into a shortcut. This has now spread to my computer and every time I plug in any sort of external drive the same happens, everything is turned into shortcuts! I'm generally good with computers but I'm not sure with this one. I know that Microsoft blocked the 'Autorun ' feature on Windows 7 as it was too easy for viruses to spread, so how is this one spreading?! I've looked it up a lot and nothing is working. I need help ASAP as it is important for school.