Unable to update Yosemite to Sierra after dual boot with rEFInd

[Rich]

Hi,

I have a dual boot with OSX Yosemite and Kali using rEFInd. When I run the Sierra installer I get - "This disk cannot be used to start up your computer"

I've tried the trick described here but disk utility won't let me change the partition size. I've run a verify on the disk and everything looks fine.

Suggestions...?

[Roderick W. Smith]

I can imagine a couple of possible causes of this problem, each of which would have a different solution:

• The Sierra installer dislikes rEFInd -- It could be that the Sierra installer sees that a non-Apple tool is in charge of the boot process, and is therefore refusing to run. To work around this problem, you could use the Startup Disk item in System Preferences to set OS X to boot directly, thus bypassing rEFInd. After installing Sierra, you'd need to re-install rEFInd, or at least reset the existing rEFInd as the default boot option. (You'd basically treat it as if you were recovering from a boot coup.)
• When installing Kali, you didn't include adequate unpartitioned space between partitions -- This is the issue that the page to which you pointed addresses. Basically, Apple's installers want to see 128 MiB or more of unpartitioned space after the partition to which the OS is being installed. If Apple's Disk Utility won't let you adjust the OS X partition size, you might try doing the same thing using GParted in Kali. Alternatively, you could shrink the partition that follows the OS X partition; but moving the start point of a partition is almost always riskier and more time-consuming than moving the end point. Backing up important data from the disk, and especially from the partition(s) you modify, is important when modifying partitions in this way, or when installing an OS.

Overall, I'd say that inadequate unpartitioned space following the OS X boot partition is the more likely explanation. I don't recall having to reset OS X to be the default OS to boot when I updated my own MacBook to Sierra.

[Andrew Maxwell]

Ah, I'm experiencing this now, only trying to update Sierra to High Sierra Beta. I have rEFInd installed and working quite well, very pleased with it overall. However it has been problematic for this update.

When I attempt to update, I get this: http://i.imgur.com/SFKTky1.png

No problem then, right? Just follow the adivce at https://support.apple.com/en-us/HT203482. However, when I attempt to do this, either by creating a new partition, or shrinking my partition inlcuding Sierra, I get this: http://i.imgur.com/DWFdwY5.png

If I can suggest, Rich above agrees with your advice in the second part of your response, about inadequate partition space. What he's asking, like me, is... what to do about Disk Utility not letting you partition the drive?

Any further advice?

[Roderick W. Smith]

FWIW, I did a High Sierra install over the weekend and had no problems with it; however, I installed to an external USB disk (not a flash drive; a regular disk). It works fine with rEFInd, with the caveat that the computer boots straight to High Sierra when its disk is plugged in, bypassing rEFInd. I haven't invested the time into figuring that out.

As to problems with resizing an existing macOS partition, I can't really say what's wrong. The message makes it sound like you don't have enough free space on the partition to shrink it, but error messages like that are often misleading. You might try using another tool, like GParted in a Linux distribution. Be aware, though, that any partition resizing operation is inherently at least a little bit dangerous. You'd do well to back up the partition before attempting to resize it.