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

Popular Stories

airpods pro 3 purple

New, Higher End AirPods Pro Coming This Year

Tuesday January 20, 2026 9:05 am PST by
Apple is planning to debut a high-end secondary version of AirPods Pro 3 this year, sitting in the lineup alongside the current model, reports suggest. Back in September 2025, supply chain analyst Ming-Chi Kuo reported that Apple is planning to introduce a successor to the AirPods Pro 3 in 2026. This would be somewhat unusual since Apple normally waits around three years to make major...
smaller dynamic island iphone 18 pro Filip Vabrous%CC%8Cek

iPhone 18 Pro Leak: Smaller Dynamic Island, No Top-Left Camera Cutout

Tuesday January 20, 2026 2:34 am PST by
Over the last few months, rumors around the iPhone 18 Pro's front-panel design have been conflicted, with some supply-chain leaks pointing to under-display Face ID, reports suggesting a top-left hole-punch camera, and debate over whether the familiar Dynamic Island will shrink, shift, or disappear entirely. Today, Weibo-based leaker Instant Digital shared new details that appear to clarify the ...
iOS 27 Mock Quick

iOS 27 Will Add These 8 New Features to Your iPhone

Sunday January 18, 2026 3:51 pm PST by
iOS 27 is still many months away, but there are already plenty of rumors about new features that will be included in the software update. The first beta of iOS 27 will be released during WWDC 2026 in June, and the update should be released to all users with a compatible iPhone in September. Bloomberg's Mark Gurman said that iOS 27 will be similar to Mac OS X Snow Leopard, in the sense...
14 inch MacBook Pro Keyboard

MacBook Pro Buyers Now Facing Up to a Two-Month Wait Ahead of New Models

Sunday January 18, 2026 6:50 pm PST by
MacBook Pro availability is tightening on Apple's online store, with select configurations facing up to a two-month delivery timeframe in the United States. A few 14-inch and 16-inch MacBook Pro configurations with an M4 Pro chip are not facing any shipping delay, but estimated delivery dates for many configurations with an M4 Max chip range from February 6 to February 24 or even later. At...
Liquid Glass App Store Feature

App Store and Apple TV Experiencing Outage

Tuesday January 20, 2026 4:36 pm PST by
Apple's App Store, iTunes Store, and Apple TV service are experiencing an outage at the current time, according to Apple's System Status page. Apple says that some users may be experiencing issues with the App Store and iTunes Store. Apple also says some users may be seeing intermittent issues with Apple TV. The Apple TV Channels feature is down too, and users may be unable to access some...

Top Rated Comments

HiRez Avatar
64 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
64 months ago
Especially given how many Mac users still have a 128GB SSD.
Score: 25 Votes (Like | Disagree)
ouimetnick Avatar
64 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
64 months ago
Apple SW QA still needs way more attention, way too many updates across ...
Score: 21 Votes (Like | Disagree)
Matthew.H Avatar
64 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
64 months ago
Newbie mistake. What's going on over there?
Score: 17 Votes (Like | Disagree)