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I have a Nero Disk Image(.nrg) File and I would like to mount it on OSX to copy it's contents. I've tried to rename to .iso and to use NRG2ISO with no luck.

Any tips ?

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up vote 1 down vote accepted

A little googling led me to this thread on

It appears that if the ISO is a single session CD image you can just knock the first 600 bytes off with a terminal command and it'll be readable as an ISO (change file type to .iso after performing the command).

I'd recommend making a backup of the .nrg file before trying this though!

$ dd if=image.nrg of=cdrom.iso bs=512 skip=600

(↑ credit to balamw on macrumors forums)

Also, If you're just looking to extract pictures from the disk, File Juicer may also be worth a look!

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Thank you for the tip, but this didn't work for me :( (when I mount the resulting iso I get 'not recognized') – George Profenza Jul 28 '11 at 14:30
dd just reads the in file (if) so it's not writing to the nrg file in this case. – bmike Jul 28 '11 at 16:54

Had the same experience as the OP. Tried using nrg2iso, tried renaming the file to .iso and also tried the dd command from that MacRumors thread. Nothing worked.

However, I then found nrg4iso which worked perfectly! The project has been abandoned since 2007 but it still works.

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I tried nrg4iso, but it erred with the following message: "Source is a Nero DAO (Disc at once) image with 2 session(s)." – asbjornu Jan 3 '14 at 6:21

dd variant not work for me. So, i find another one with poweriso:

Use: ./poweriso convert ~/Desktop/image.nrg -o ~/Desktop/image.iso -ot iso

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With .nrg images from audio CDs, the solutions proposed in the other answers do not work (e.g. failing with Source is a Nero DAO (Disk at once) with 1 session(s) ).

However, the commercial Deamon Tools are now available for Mac OSX. Using these, you can mount the .nrg as an Audio CD.

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