Aux.class "could not find this item"

I somehow managed to get this file unzipped, and into one of my folders. However, when I try to move or delete it, it can't be found. How can I get rid of it?

I've tried deleting, moving, and renaming it. I've restarted the computer, used kill box, and have read that its an invalid file name in Windows. Does anyone know how I can delete this file so I'm not constantly getting errors when manipulating the folder that it is in?

As for how I managed to create it in the first place; I used an installer to mod the Minecraft.jar, Minecraft crashed after the installation. The installer made a backup of .jar file, and so I used the IZArc to unzip that backup, which unzipped the aux.class which was part of the backup. It asked if I wanted to replace the aux.class file, and I told it yes thinking nothing of it.