Autorun is a common Worm that spreads on removable drives.
Variants of Autorun are worms that spread by copying themselves into the root directories of hard drives and other writable media such as USB memory sticks. It would delete most useful programs, lock the Task Manager, and become the administrator. It would eat up all useful space by replicating itself on every file in an attempt to clog the computer.
This worm and variants create an autorun.inf file in the root directories of drives they want to infect. Removing this virus may be impossible.