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.
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.
Popular Stories
Apple is expected to unveil iOS 27 during its WWDC 2026 keynote on June 8, and there are already many rumored features and changes for iPhones.
The first developer beta of iOS 27 will likely be available immediately following the keynote, and a public beta typically follows in July. Following beta testing, the software update should be released to all users with a compatible iPhone in...
Apple refreshed the 14-inch and 16-inch MacBook Pro with M5 Pro and M5 Max models in March 2026, but depending on your needs and interests, you might want to skip this generation because there's something better in the works.
The M5 Pro and M5 Max MacBook Pro models have faster chips, but the same design that Apple has used since 2021. An updated design with new display technology and faster ...
Apple will unveil its latest software platforms during its WWDC 2026 keynote on Monday, June 8, and one of them will be macOS 27 for the Mac.
The first developer beta of macOS 27 will likely be available immediately following the keynote, and a public beta typically follows in July. Following beta testing, the software update should be released to all users in September.
macOS 26 is known ...
