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

iphone 17 models

No iPhone 18 Launch This Year, Reports Suggest

Thursday January 1, 2026 8:43 am PST by
Apple is not expected to release a standard iPhone 18 model this year, according to a growing number of reports that suggest the company is planning a significant change to its long-standing annual iPhone launch cycle. Despite the immense success of the iPhone 17 in 2025, the iPhone 18 is not expected to arrive until the spring of 2027, leaving the iPhone 17 in the lineup as the latest...
duolingo ad live activity

Duolingo Used iPhone's Dynamic Island to Display Ads, Violating Apple Design Guidelines

Friday January 2, 2026 1:36 pm PST by
Language learning app Duolingo has apparently been using the iPhone's Live Activity feature to display ads on the Lock Screen and the Dynamic Island, which violates Apple's design guidelines. According to multiple reports on Reddit, the Duolingo app has been displaying an ad for a "Super offer," which is Duolingo's paid subscription option. Apple's guidelines for Live Activity state that...
Low Cost A18 Pro MacBook Feature Pink

Apple's 2026 Low-Cost A18 Pro MacBook: What We Know So Far

Friday January 2, 2026 4:33 pm PST by
Apple is planning to release a low-cost MacBook in 2026, which will apparently compete with more affordable Chromebooks and Windows PCs. Apple's most affordable Mac right now is the $999 MacBook Air, and the upcoming low-cost MacBook is expected to be cheaper. Here's what we know about the low-cost MacBook so far. Size Rumors suggest the low-cost MacBook will have a display that's around 13 ...
govee floor lamp

CES 2026: Govee Announces New Matter-Connected Ceiling and Floor Lights

Sunday January 4, 2026 5:00 am PST by
Govee today introduced three new HomeKit-compatible lighting products, including the Govee Floor Lamp 3, the Govee Ceiling Light Ultra, and the Govee Sky Ceiling Light. The Govee Floor Lamp 3 is the successor to the Floor Lamp 2, and it offers Matter integration with the option to connect to HomeKit. The Floor Lamp 3 offers an upgraded LuminBlend+ lighting system that can reproduce 281...
airpods pro 3 glitter

AirPods New Year's Deals Include Up to $99 Off AirPods Max, AirPods Pro 3, and AirPods 4

Sunday January 4, 2026 8:04 am PST by
Now that the calendar has flipped over into January, steep discounts on popular Apple products have become more rare after the holidays. However, if you didn't get a new pair of AirPods recently and are looking for a model on sale, Amazon does have a few solid second-best prices this week. Note: MacRumors is an affiliate partner with some of these vendors. When you click a link and make a...
Belkin 25W Battery magnetic

CES 2026: Belkin Announces Magnetic Ring Power Bank, Modular Dock, and More

Sunday January 4, 2026 3:02 pm PST by
Belkin today announced a range of new charging and connectivity accessories at CES 2026, expanding its portfolio of products aimed at Apple device users. UltraCharge Pro Power Bank 10K with Magnetic Ring The lineup includes new Qi2 and Qi2.2 wireless chargers, magnetic power banks, a high-capacity laptop battery, and USB-C productivity accessories, with an emphasis on higher charging...
Low Cost MacBook Feature A18 Pro

Low-Price 12.9-Inch MacBook With A18 Pro Chip Reportedly Launching Early This Year

Friday January 2, 2026 9:08 am PST by
Apple plans to introduce a 12.9-inch MacBook in spring 2026, according to TrendForce. In a press release this week, the Taiwanese research firm said this MacBook will be aimed at the entry-level to mid-range market, with "competitive pricing." TrendForce did not share any further details about this MacBook, but the information that it shared lines up with several rumors about a more...
Clicks Communicator Feature

'Clicks Communicator' Unveiled — Will You Carry This With Your iPhone?

Friday January 2, 2026 6:35 am PST by
The company behind the BlackBerry-like Clicks Keyboard accessory for the iPhone today unveiled a new Android 16 smartphone called the Clicks Communicator. The purpose-built device is designed to be used as a second phone alongside your iPhone, with the intended focus being communication over content consumption. It runs a custom Android launcher that offers a curated selection of messaging...

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)