Revised macOS Big Sur 11.2.1 Update Properly Checks Free Available Space to Prevent Installation Errors

When upgrading to macOS Big Sur, there was an error that would cause issues if there wasn't enough storage space available. Unfortunately, the update was not checking if there was enough free space before the installation started, which could lead to data loss.

First Look Big Sur Feature2
The free space issue has been addressed in a revised macOS Big Sur 11.2.1 update that was released this morning. According to Mr. Macintosh, the new update checks to make sure there is enough available storage space before installation starts.


If you don't have enough free space, the installer will say "There is not enough free space on the selected volume to upgrade the OS," and it will let you know how much additional space is required.

The new update that was released today is available only if you had not previously installed macOS Big Sur 11.2.1.

Related Forum: macOS Big Sur

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Top Rated Comments

HiRez Avatar
55 months ago
Wow, this is a pretty basic thing to miss, with potentially terrible consequences. I mean checking free space before you install, wouldn't that be on the standard checklist since forever?
Score: 36 Votes (Like | Disagree)
NewUsername Avatar
55 months ago
Especially given how many Mac users still have a 128GB SSD.
Score: 25 Votes (Like | Disagree)
ouimetnick Avatar
55 months ago
Why does an OS take up 35GB of space? I remember back when Snow Leopard cam out Apple bragged that it took less space than it's predecessor. Try trimming some of the bloat out of the next macOS release.
Score: 23 Votes (Like | Disagree)
jz0309 Avatar
55 months ago
Apple SW QA still needs way more attention, way too many updates across ...
Score: 21 Votes (Like | Disagree)
Matthew.H Avatar
55 months ago

Choosing storage space during purchasing is the responsibility of the buyer, not the seller. When people cheap out on storage space they are entering at their own risk.
It doesn't help that Apple has frankly been stingy on storage for years. They've only just recently made 256GB the minimum when it should have been the standard base at least 5 years ago.
Score: 20 Votes (Like | Disagree)
now i see it Avatar
55 months ago
Newbie mistake. What's going on over there?
Score: 17 Votes (Like | Disagree)