Couldn't mount install ESD error - Yosemite

[tomplums]

So I went for it - purchased all the hardware (still currently building) and decided to create my UniBeast install drive. I've failed at the first hurdle, so it seems. I need some help.

I keep getting Couldn't mount install ESD error when attempting to make my USB drive.



Now I have googled and searched the forum for a few hours this morning regarding this error. There are some users reporting the same issue. They've all been told to re-download Yosemite from the App Store so I've followed that advice and downloaded it three times now, making sure I trash and delete any old copies. Still receiving the same error.

I've attempted to create the disk on two computers:

First - MacBook Pro Mid 2010 running 10.10.1
Second - Mac Pro 2006 1,1 running 10.7.5 (I installed the supplemental update as advised in UniBeast troubleshooting thread)

Neither machine is able to create the USB - both receive the same issue. When copying the Yosemite install from the Macbook to my Pro I'm zipping the file to avoid corruption and again, I've tried it three times with the fresh Yosemite installer.

I'm guessing I need to run UniBeast on a newer mac to create the USB? Just wanted to ask here before I try and find a newer machine

TIA

Tom

 

[MacMan]

Did you delete the app before downloading again? If you haven't do that as I've seen errors propagate that way.

Otherwise try to manually mount the DMG from the command line using this command:

hdiutil attach /Applications/Install\ OS\ X\ Yosemite.app/Contents/SharedSupport/InstallESD.dmg

If it mounts then unmount it and then run UniBeast again.

 

[tomplums]

Success - thank you Mac Man.

I performed a Secure Empty Trash on the machine, then re-downloaded Yosemite.

On to the next stage...

T