Some time ago I downloaded a QuickLook plugin that allowed me to look at the files in an ISO called Suspicious Package. I used this to inspect the contents of an ISO and it displayed this:

enter image description here

And Finder says that the ISO is 428.1 MB. So the ISO definitely contains some files, but when I mount it by double-clicking on it, there's nothing in it; I get this:

enter image description here

I went into Disk Utility and clicked "Verify Disk" and I get this:

Verifying volume "PROSHOW DVD"
Checking file system
fsck_udf: Cannot read directory entry at offset 236: Undefined error: 0
fsck_udf: Directory Checking was bad!
** Checking Hierarchy
** Filesystem is dirty and non-repairable
Error: This disk needs to be repaired. Click Repair Disk.

The "Repair Disk" button is grayed out though. My question is, how do I get at the files in the ISO?

1 Answer 1


ISO images typically contain more than one file system, the original ISO9660 file system for CD-ROMs (hence "ISO"), the "Joliet" extension to it for long filenames, and sometimes UDF or even a HFS+ file system. It's possible that one of them is corrupt, but the others are fine.

You could try explicitly mounting with the ISO9660 file system driver, as the UDF file system seems to be damaged. First, open a Terminal window. Attach the image without mounting:

hdiutil attach -nomount /path/to/image.iso

This should output the name of the disk device node, e.g.:


Create a mountpoint for the filesystem, e.g.

mkdir /Volumes/rescue

Then try mounting the device there, e.g.:

mount_cd9660 /dev/disk2 /Volumes/rescue

If it worked, it won't output anything, but the disk should be visible in Finder. (You can "eject" it via Finder when you're done)


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