Trying to use a Mojave installer USB drive to install OSX on an external HD but only get a "macOS Install Data" folder

[David Mansfield]

The title says it all-- I've looked this up extensively on the web, but have found no solutions.

I am trying to use a USB stick Mojave installer I created with "Install Disk Creator" to install a clean copy of Mojave on an empty external hard drive (USB 3), and the install won't complete. Instead I get a folder named "macOS Install Data" on the external drive. I've tried reformatting the drive as APFS as well as the old Mac OS Extended, and have tried installing from the Recovery mode of my computer (a Mac Pro 5,1 running Mojave with a Metal graphics card flashed for Mac), and have the same problem no matter what I do.

Is there any way to force the install to complete?

 

[flaubert]

I think that there are several possibilities for what is going wrong. You might want to go over to the Mac Pro sub-forum on this site, and look for the thread by tsialex about what it takes to install Mojave; briefly, you have to have the right Metal-compatible graphics card, and you have to go through the full update process in High Sierra to get the Mac Pro firmware up to 144.0.0.0, even though your eventual destination is Mojave.

Here is a link to that thread: MP 5,1: What you have to do to upgrade to Mojave

If you still have problems, it is probably better to post in that sub-forum, since just about everyone there has gone through the process.

 

[David Mansfield]

Thanks, I actually already have Mojave up and running on my Mac Pro 5,1 with a Metal graphics card. What I had wanted to do was create a Mojave "rescue" disk on an external USB hard drive. After trying a million things, I gave up and used TechTool Pro 13 to create one.

By the way, once I created my "rescue" disk, I could not boot from it using the PCI-based USB 3.0 card I use. I have to plug the drive into one of the original USB 2.0 ports (on the front or back) of the Mac Pro.

 

[flaubert]

OK, yes, I get what you were trying to do. I'm glad you found a way around it. I've seen recommendations in various forum threads that when it comes to the later OS versions, like Mojave and above, you want to do your install to a SATA drive that is the only one in the box, with no PCIE cards other than the graphics card installed (I think that the tsialex thread even states this). Finicky! I'm not that familiar with what Tech Tool Pro can do, but if I were trying accomplish the goal you listed I would put a scratch hard disk in a SATA sled, remove all other drives, remove all non-essential PCIE cards, and then do the install to that hard drive. Once complete, I would use Carbon Copy Cloner to copy it to the USB3 hard drive.

Interesting that your PCIE card that offers the USB3 ports doesn't support booting, hmm.

 

[David Mansfield]

All I can say is I can't wait for a Mac Mini with 64 GB RAM (or more), then goodbye cheese-graters