High Quality Content by WIKIPEDIA articles! An autorun.inf file is a text file that can be used by the AutoRun and AutoPlay components of Microsoft Windows Operating systems. For the file to be discovered and used by these components, it must be located in the root directory of a volume. As Windows has a case-insensitive view of filenames, the autorun.inf file can be stored as AutoRun.inf or Autorun.INF or any other case combination.