SillyFDC is a relatively harmless worm, which is designed only to spread and therefore does not carry any destructive payload. The parasite propagates mostly through floppy disks. Once executed, it displays a fake error message ("File Corrupted. Re-install") and installs itself to the system. SillyFDC periodically attempts to copy itself to a floppy disk. If the user terminates the worm, it displays another fake error message ("This is a critical system process. Task manager cannot end this process") and restarts itself. SillyFDC automatically runs on every Windows startup.