External bootable SSD won't mount

Question

Level 1

8 points

External bootable SSD won't mount

Hello

I basically installed OS Mojave on an external SSD (Lacie Portable SSD v2) the other day. The drive is connected to my Macbook Pro Retina late 2013 machine, running OS 10.9.5, through one of the USB 3.0 ports on the machine.

The installation process went fine, I started formatting the Lacie drive as Mac OS Extended (Journaled), then I downloaded OS Mojave from the App Store and followed the process of installation. After the installation was done I booted right into OS Mojave, all good.

Booting into Mavericks again (internal drive), the external drive with Mojave doesn't show up and according to disk utility it isn't mounted (greyed out, see attachment). Tried restarting the machine, different cable, the other available USB port, still won't mount.

However, it does mount on my Macbook Pro 2011 with High Sierra, so the drive is working and shows up as "OS Mojave", which I named it. Anyone knows what might be going on, why won't my Macbook Pro with Mavericks mount it? Is it the OS?

Disk utility in Mavericks below, Mojave drive is greyed out. I also tried "force mounting" it there, nothing.

Marius

MacBook Pro 15″, 10.13

Posted on Dec 1, 2021 1:07 PM

Reply

Answer 1

Best reply

Eau Rouge

Level 8

42,554 points

Dec 1, 2021 10:26 PM in response to mariuste

Older OS's like Mac OS X Mavericks up to Mac OS X El Capitan cannot see macOS's on Disks that are formatted as APFS.

With the introduction of macOS High Sierra Apple introduced the new APFS file system, that is why it is greyed out in

Disk Utility.

When you are booted in Mavericks and attach the Mojave SSD you will get a warning that the disk is not readable press

the Ignore button, do not press Initialise, you will erase the SSD.

To boot from Mavericks to the Mojave SSD Restart your mac while pressing the option/ alt key.

In a minute or two you will see the Boot Manager screen select the Mojave SSD and press Return.

When running Mojave and wanting to switch back to Mavericks open System Preferences> Startup Disk

select Mavericks and press Return.

Why are you still running Mavericks anyway.

Reply

Answer 2

mariuste Author

Level 1

8 points

Dec 2, 2021 12:04 PM in response to Eau Rouge

Thank you for the information, Eau Rogue. I suspected it was an apfs hpfs issue. I wasn’t aware the drive was automatically converted to apfs though, so thank you for clarifying this. The reason for that I am still on Mavericks is that I am using this machine for music production and with this OS I have access to my old unfinished 32 bit projects while working on newer ones as well. Mavericks haa been running smoothly for me so I haven’t had the urge to upgrade. Until know. I will put Mavericks on my external eventually and have Mojave on the internal. Best regards, Marius

Reply

External bootable SSD won't mount

Similar questions