ISODisk is a freeware tool that lets you create ISO file as well it can also create up to 21 virtual drives. You can mount up to 20 ISO image with the help of ISODisk free software. After installing it on your computer, when you will the tool, you will found only two menus, one is for mounting the ISO file and another for creating the ISO image from CD-ROM.
ISODisk is a free and powerful ISO disk image file tool that allows you to create virtual CD/DVD driver up to 20 drivers, and also can mount an .ISO disk image and access the files on it. This program can quickly create ISO image file from CD/DVD-ROM.
The app is only compatible with Windows XP/2003/Vista and can be downloaded from here.
While testing the different ISO mounting freeware software, I found Virtual CloneDrive is the best and also supports Windows 10. ImgBurn, PowerISO, WinCDmu, Microsoft Virtual CD-ROM Control Panel, and DVDFab Virtual Drive are another free apps that lets you mount the image file.