Can't Update to the macOS 15.4 RC? Here's Why

Some Mac users who have an M4 MacBook Air or M4 Max/M3 Ultra Mac Studio are unable to update to the latest macOS 15.4 beta that came out today, according to complaints on Reddit.

M4 MacBook Air 13 and 15 inch Feature
Multiple people have reported that attempting to download and install the macOS 15.4 release candidate results in an error message. "macOS could not be downloaded. Make sure you're connected to the internet and try again, or contact Apple support for assistance," reads the error.

It turns out that Apple failed to provide the appropriate decryption key for the M4 ‌MacBook Air‌ and ‌Mac Studio‌ models to install the update. Apple encrypts its software updates and a server-side decryption key is required for installation. The key for new Macs is not available from Apple's software server at this time.

If you have one of the new Macs that's running the software that it came with when it arrived, you won't be able to update to the macOS Sequoia 15.4 release candidate until Apple fixes the issue.

This problem will not affect new ‌MacBook Air‌ and ‌Mac Studio‌ models that were previously running macOS 15.4 beta 4, as these machines can install the release candidate.

Related Forum: macOS Sequoia

Popular Stories

Aston Martin CarPlay Ultra Screen

Apple's CarPlay Ultra to Expand to These Vehicle Brands Later This Year

Sunday February 1, 2026 10:08 am PST by
Last year, Apple launched CarPlay Ultra, the long-awaited next-generation version of its CarPlay software system for vehicles. Nearly nine months later, CarPlay Ultra is still limited to Aston Martin's latest luxury vehicles, but that should change fairly soon. In May 2025, Apple said many other vehicle brands planned to offer CarPlay Ultra, including Hyundai, Kia, and Genesis. In his Powe...
Apple Logo Black

Apple's Next Launch is 'Imminent'

Sunday February 1, 2026 12:31 pm PST by
The calendar has turned to February, and a new report indicates that Apple's next product launch is "imminent," in the form of new MacBook Pro models. "All signs point to an imminent launch of next-generation MacBook Pros that retain the current form factor but deliver faster chips," Bloomberg's Mark Gurman said on Sunday. "I'm told the new models — code-named J714 and J716 — are slated...
Apple MacBook Pro M4 hero

New MacBook Pros Reportedly Launching Alongside macOS 26.3

Sunday February 1, 2026 5:42 am PST by
Apple is planning to launch new MacBook Pro models with M5 Pro and M5 Max chips alongside macOS 26.3, according to Bloomberg's Mark Gurman. "Apple's faster MacBook Pros are planned for the macOS 26.3 release cycle," wrote Gurman, in his Power On newsletter today. "I'm told the new models — code-named J714 and J716 — are slated for the macOS 26.3 software cycle, which runs from...
iOS 26

iOS 26.3 and iOS 26.4 Will Add These New Features to Your iPhone

Tuesday February 3, 2026 7:47 am PST by
We are still waiting for the iOS 26.3 Release Candidate to come out, so the first iOS 26.4 beta is likely still at least a week or two away. Following beta testing, iOS 26.4 will likely be released to the general public in March or April. Below, we have recapped known or rumored iOS 26.3 and iOS 26.4 features so far. iOS 26.3 iPhone to Android Transfer Tool iOS 26.3 makes it easier...
iOS 26 Home Feature

Apple Gives Final Warning to Home App Users

Tuesday February 3, 2026 8:55 am PST by
In 2022, Apple introduced a new Apple Home architecture that is "more reliable and efficient," and the deadline to upgrade and avoid issues is fast approaching. In an email this week, Apple gave customers a final reminder to upgrade their Home app by February 10, 2026. Apple says users who do not upgrade may experience issues with accessories and automations, or lose access to their smart...

Top Rated Comments

kalimdor Avatar
11 months ago
Next up: Apple accidentally releases macOS Snow Leopard on all Apple Silicon Macs.
Score: 18 Votes (Like | Disagree)
sw1tcher Avatar
11 months ago

Can't Update to the macOS 15.4 RC? Here's Why
It just works. And sometimes it doesn't.™
Score: 11 Votes (Like | Disagree)
Corefile Avatar
11 months ago
Usually they want to prevent you from DOWNGRADING. Oh Apple.
Score: 8 Votes (Like | Disagree)
flybass Avatar
11 months ago
To be fair- we’re talking beta software.
Score: 7 Votes (Like | Disagree)
Corpuscle Avatar
11 months ago
Apple has been making more and more mistakes lately. They are really deteriorating. Did Timmy blindly cut 1000's of engineers to increase his income?
Score: 7 Votes (Like | Disagree)
Astuces iOS Avatar
11 months ago

Next up: Apple accidentally releases macOS Snow Leopard on all Apple Silicon Macs.
Hey that's a secret move for WWDC25 !
Score: 3 Votes (Like | Disagree)