Installing Mojave - circle with /

Sorry to destroy that theory... I've tried to install Mojave onto a SanDisk Extreme 900 that's directly connected to my late 2016 tMBP 15 with its original cable and it faled in the same way as for the OP. I also tried with an older WD Passport connected using a USB-A to C dongle and that also failed in the same way.

not sure that destroys the theory, maybe expands it a bit. Per other posts in this thread seems like installing on SSD device is a problem also (your device is SSD right?). Also, as noted below, I had a problem installing on G-Drive mobile usb-c using the included usb-c to usb-c cable but used a different (usb-c to usb-c) cable and it worked fine, so I guess there are problems with cables in general not just usb-c to usb-3?

I had issues installing to an external USB-C WD SSD 1TB drive connecting directly to my MacBookPro 2016 TB. I tried with a SanDisk USB-C thumb drive and that worked, but was much slower. Today I tried the same WD SSD drive, but put a USB hub between the drive and the computer (a 4-port USB3 with A ports, not powered) and the install seemed to go further, but hung when the progress bar looked to be complete. I let it sit for about an hour with no movement. I rebooted and everything seemed to be installed and am writing this post from 10.14. Rebooting with the drive directly connected via USB-C still produces the O+/ error. For now, it needs the hub in there to boot correctly

So it seems to be how the OS talks to USB drives that makes the difference. Maybe some kind of timing issue?

-Jeremy A Moore

I spent some time yesterday doing test installs on 3 external usb-c drives with my MBP 2016 notebook. Used the same procedure in all 3 cases:

(1) boot into MBP 10.13.5 partition on its native drive

(2) attach "test" drive using its manufacturer provided usb-c to usb-c cable

(3) erase test drive and install 10.13.5 from high sierra install app

(4) during the intall setup attached TM backup volume (containing backup from MBP native drive) to load user account, applications, etc

(5) after HS 10.13.5 fully installed on "test" drive download 10.14 beta install app to it and install 10.14

In all 3 cases steps 1-4 went fine but step 5 failed after proceding through most of install, showing the dreaded cirlce-/ screen.

So then (again in all 3 cases):

shutdown computer

replace manufacture's usb-c to usb-c cable with my spare cable which is an innergie 2meter usb-c to usb-c (product code ACUSBC SL 200)

reboot computer

In all 3 cases the install then finished with no further problems and the drive was fully usable with 10.14

Not sure what to make of this other than all of the drives are fully capable of running the beta but most cables cause problems.

Looks like Beta 2 fixed this for me. Installed directly to my WD SSD external USB-C drive with no issues other than some blinking of the progress bar at one point.

Works for me now too on the MBP via USB C.

:-)

also for me. Updated each of my 3 test drives and they now run with manufacturer-supplied usb-c to usb-c cables on MBP 2016.

well it was fun while lasted but this problem re-appeared for me when updating to beta 3 on external disk; cannot complete the upgrade. Hopefully not everyone else who originally had the problem will be affected by beta 3.