I don't think it's that as a separate system partition is created on the external drive. And I've never had this particular problem with previous versions of the OS. At least it hasn't bricked the Mac, as in Adrian's link, so it's unlikely to be a firmware problem.

There are a couple of kexts with Samsung in the name on my Big Sur install. I may try a fresh install, rather than an upgrade, on the external SSD to see if that boots. It's clearly not a serious problem as it boots in safe mode.

In reply to a post by TinyMongomery:

I don't think it's that as a separate system partition is created on the external drive. And I've never had this particular problem with previous versions of the OS. At least it hasn't bricked the Mac, as in Adrian's link, so it's unlikely to be a firmware problem.

There are a couple of kexts with Samsung in the name on my Big Sur install. I may try a fresh install, rather than an upgrade, on the external SSD to see if that boots. It's clearly not a serious problem as it boots in safe mode.

Have you tried an SMC reset?

Do you think its related to the USB issue reported here? Although this appears to be mainly M1 silicon and Monetrey, there are also Intel based machine affected.

Yeah. I've done all the normal troubleshooting stuff. That USB problem seems to affect external hubs, whilst this is a USB-C disk plugged directly into one of the USB-C ports. The fact that it boots in safe mode indicates some kext or program is causing it rather than a fundamental problem.

Another strange thing I discovered yesterday is that I can't clone the Monterey install to another external drive. I forget the exact error message but I think it said something about the drive not being unlocked. Strange. But that could be because I'm trying to clone a Monterey disk whilst running Big Sur.

It's not a huge deal as I've no need to upgrade right now, but I don't like it when I can't understand a problem.

Finally time to upgrade my MacBook Air (late 2014)

Missed the cutoff time for being supported...



A

In reply to a post by Pheasant:

Risk it or just go for the Big Sur 11.6.1 update....Hmmmm I wonder what will break.....

2 weeks passed now. Happy to report all good and no issues (touch wood).

In reply to a post by nonymouse:

Finally time to upgrade my MacBook Air (late 2014)

Missed the cutoff time for being supported...



A

Yeah the cutoff was early-2015 MB Air's...

In reply to a post by Pheasant:

In reply to a post by Pheasant:

Risk it or just go for the Big Sur 11.6.1 update....Hmmmm I wonder what will break.....

2 weeks passed now. Happy to report all good and no issues (touch wood).

Stability remains all good here. Most recent reboot was last week, so OK I think.

Though Apple probably warming up for a Monterey point release in the next 10 days or so....if history is any guide.

Monterey 12.1 is out tonight. 3.17GB download.

12.4 just installed. Nothing broke