Like I said in my earlier post, it works fine on my 2012 Air. It does not work on my 2017 MacBook Pro. This problem seems to affect only the 2016-2017 machines. Found a thread in Apple’s developer forum where other people are having the same issue.
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Install To External SSD?
- Thread starter PBG4 Dude
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I installed Mojave on a external SSD (Crucial MX100) connected to my 2017 iMac. No problems noted with the installation process. Running well thus far, albeit slower than what I am used to with my iMac.
I had the same issue after three hours of troubleshooting I have a solution. I unplugged the external ssd from my iMac and connected it to my MacBook Pro. I did not boot from the external SSD instead I had my MacBook do the install to the external ssd. When my MacBook finished the install and tried to boot into the external ssd I got an error. The no go sign with the slash. I plugged the external ssd back into my iMac. The iMac booted into the ssd just fine even though my MacBook wouldn’t. Weird.
I have had the same issue with a new T5 Samsung Portable SSD and the MacBookPro14,3 (15inch, 2017, Touch Bar)
Installation starts, than after 20 min it shows a stop sign and I tried pretty much every road to Rome on this one:
1. Clean install from bootable drive
2. Clean install from current OS using the installer
3. Clean install High Sierra and than upgrade
I tried HFS+ and APFS, single partition, multi partitions on disk...
But all ended with the stop sign.
For me the solution was to not use the USB-C cable that came with the drive but I used to USB-C cable from the charger.... Voila installation finished as expected and now runs like a charm. Seems that macOS is getting picky on USB-C cables
Installation starts, than after 20 min it shows a stop sign and I tried pretty much every road to Rome on this one:
1. Clean install from bootable drive
2. Clean install from current OS using the installer
3. Clean install High Sierra and than upgrade
I tried HFS+ and APFS, single partition, multi partitions on disk...
But all ended with the stop sign.
For me the solution was to not use the USB-C cable that came with the drive but I used to USB-C cable from the charger.... Voila installation finished as expected and now runs like a charm. Seems that macOS is getting picky on USB-C cables
I'm attempting to install the public beta and having issues, but NOT the flashing No symbol. File Vault-enabled 2017 MacBook, no Pro, yo. Generic USB-C port replicator (presumably fake Qac Qoc brand name). USB-A 3.1 SATA adapter to SSD. Also tried going right to USB-A flash drives.
Running the installer from the internal drive and setting it to install to the external starts off fine. When it prompts to reboot to complete installation, the computer just reboots into the internal SSD. Looking at the Startup Disk setting shows only one drive as an option, which is the internal.
Maybe I'm just running into an issue because of File Vault, or maybe it's one of the touchy USB-C cables / chipsets. At least I tried to use it. I've used the Feedback App to report it. Too bad I can't get any further so I can provide productive feedback.
P.S.
I've also tried Option booting to force its hand. Only one bootable drive.
Running the installer from the internal drive and setting it to install to the external starts off fine. When it prompts to reboot to complete installation, the computer just reboots into the internal SSD. Looking at the Startup Disk setting shows only one drive as an option, which is the internal.
Maybe I'm just running into an issue because of File Vault, or maybe it's one of the touchy USB-C cables / chipsets. At least I tried to use it. I've used the Feedback App to report it. Too bad I can't get any further so I can provide productive feedback.
P.S.
I've also tried Option booting to force its hand. Only one bootable drive.
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I can just format an external SSD to HFS+ in disk utility, then point installer for Mojave to it to install right?
Don’t need high sierra?
Internal drive is also on 10.12.6 I’d be running installer from
It’s a full OS install image so it should fire up from Sierra.
If you format to HFS+, the install will reformat to APFS.
Did exactly that and it worked!
This is a fun os to play with
Thanks ! Didn’t affect my internal drive or Sierra partition either as I expected
Dang does my startech usb-c to Sata get HOT where the connectors are hooked up to the drive. Luckily the drive and the usb-c port on my laptop are cool to the touch.