How to Install macOS 15 Sequoia Beta on an SSD - External Hard Drive

You can run macOS Sequoia from the safety of a SSD without having to overwrite your current Mac software (or risk losing data). Switching versions is as simple as choosing a startup disk.

To install you'll need to download macOS Sequoia using one of two methods:

Install Steps:

1. Use "Disk Utility" to format your external SSD (256GB+) with AFPS
2. Download macOS Sequoia Full Installer (15.0, Beta 1+)
4. Run "Install macOS 15 beta" from your Applications folder
5. Click Continue and Agree
6. Show All Disks... and Select your "External Hard Drive" and Continue
7. Copy Owner and Install (You can cancel before it finishes)
8. Your Mac will attempt to reboot (close other apps)
9. Your Mac will Install macOS 15
10. After the install finishes you may need to create a user to log in

00:00 Samsung T5 SSD
00:35 Download macOS 15
01:07 Disk Utility - Format SSD
02:26 Applications - macOS Installer
02:38 Show All Drives...
03:14 Start Installing

#macos15 #sequoia #ssd #install #fullinstaller #beta #mac #apple #macos

[PaulSolt]

Make sure you use the correct USB-C port for your Mac. Boot drives require specific ports.

[opdoraya]

I’m my m1 mac I tried upgrade Mac as above but in the end I got message the version of macOS on the selected disk needs to be reinstalled. use recovery to reinstalls macOS or select another startup disk. I tried by recovery & by installer package of sequoia & also clean reinstall but every time getting same message in the end. I don't want to install on Machintosh HD, so I tried on ext ssd. please guide how to resolve this. is there any thing Xcode requirement etc.

[motionlightepic]

My installation of macOS Sequoia is load and doing is thing, how it keep on stopping at '' about 28 minutes remaining '' for hours and there no progress. I tried to restart all over again, it keeps on stopping on the point( about 28 minutes remaining ) PLS help!!😭

[tperki]

Disappointing you ended the video like you did. I wanted to see the post install process. I've heard many instances where the install fails with M series devices.

[Gamingwithcameraman-nhcp]

Can I install macOS sequoia on external hard drive

[gregbenzphotography]

After the install (to an external SD flash card), the installer says it will restart to finish. It restarts normally as if you weren't installing anything. No further errors or messages. When inspecting the external target drive, the users folder is empty (despite choosing to copy settings for the selected user). Then when trying to set the external beta/boot disk as the target, there is a warning "The version of macOS on the selected disk needs to be reinstalled. Reinstall macOS or select another startup disk." Host machine is Apple Silicon and have checked boot settings in the recovery partitition. Any idea what causes this scenario and how to resolve it?

[marat]

Csn I install macOS on external usb SSD and boot it on mac air m2?

[TheiTE]

Hi, is this demo on an Apple Silicon machine, if yes, which one?