Mount of outer dmg failed

chicago_mike · Jul 10, 2015

Hey all,

I keep getting this error. I have formatted my usage to GUID. And have downloaded the El Crapitan Beta, but overtime I try to do the sudo copy method. I get Mount of outer dmg failed.

Is it as easy as getting a different usb stick or could it be the physical usb port needs to be different? Or, could it be a bum download?

The most likely issue is , well, the most likely issue, I just don't know what it would be.

Stork · Jul 10, 2015

From where did you download the Public Beta?

chicago_mike · Jul 10, 2015

Apple. Used my redeem code.

tonymacx86 · Jul 10, 2015

chicago_mike said:
Hey all,

I keep getting this error. I have formatted my usage to GUID. And have downloaded the El Crapitan Beta, but overtime I try to do the sudo copy method. I get Mount of outer dmg failed.

Is it as easy as getting a different usb stick or could it be the physical usb port needs to be different? Or, could it be a bum download?

The most likely issue is , well, the most likely issue, I just don't know what it would be.

This actually happened to me the first time with the Clover method. Erase the USB and try again- it worked the 2nd time for me with the same 8GB USB 2.0 stick.

chicago_mike · Jul 10, 2015

Okay, I'll try it again. I'm patient. =)

Oh, I did install the latest clover on my build. But I am not sure what to change on it. Since my setup is a dual 1366..not the most usual.

I usually just leave the unibeast usb stick in my system and boot off that. Choosing any DSDT or DSDT Free mucks up my firewire for some reason. =(

Anyways, I will keep on keepin on.

degofedal · Jul 13, 2015

Same problem here. Tried re-downloading a couple of times from the App Store on both my Macbook Air and my Hackintosh. Tried using different USB keys in different USB ports. Same error every time unfortunately...

I've always had a thing about clean install vs. upgrade, so would love to be able to do a clean install with a bootable El Capitan USB key.

chicago_mike · Jul 13, 2015

Dego,

I got a successful usb stick made using the method. I ended up using a 16 Gig stick.

Specifically: Sandisk Cruzer Glide 16GB

ALL of my 8 gig sticks gave me errors. GUID, MBR, didn't matter. Only the 16GB stick worked for me.

macdja38 · Jul 14, 2015

I had the same problem... I tried on two separate computers on more usb sticks than I can count on one hand including trying to install it on an internal HDD. Eventually the thing that worked for me was using sudo su then running the command without the sudo. May have just been a coincidence but...

kylerphillip · Jul 14, 2015

chicago_mike said:
Hey all,

I keep getting this error. I have formatted my usage to GUID. And have downloaded the El Crapitan Beta, but overtime I try to do the sudo copy method. I get Mount of outer dmg failed.

Is it as easy as getting a different usb stick or could it be the physical usb port needs to be different? Or, could it be a bum download?

The most likely issue is , well, the most likely issue, I just don't know what it would be.

Same problem here, using SanDisk SDCZ48-032G-U46 Ultra USB Flash Drive USB 3.0 (32GB)

kylerphillip · Jul 14, 2015

kylerphillip said:
Same problem here, using SanDisk SDCZ48-032G-U46 Ultra USB Flash Drive USB 3.0 (32GB)

Actually, the attached worked for me (see attached image):

Re-download Public Beta from App Store
In Terminal type sudo su press return
Then type the /Applications etc... command

Search

Mount of outer dmg failed

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