How many encrypted HFS+ drives are still sitting in drawers, archive rooms, and project cabinets with data their owners assume will remain readable on future Macs?
Apple has now put a clock on that assumption. Starting with macOS 28, encrypted Mac OS Extended volumes will no longer be supported, according to 9to5Mac . Users who still rely on those volumes will need to decrypt them or reformat them before depending on them under Apple’s next storage rules.
Apple’s own support language is blunt:
“In macOS 28 and later, the Mac OS Extended file system format will be supported only for volumes (disks and other storage devices) that aren’t encrypted.”
That does not mean every old external drive dies. It means one specific combination is on the chopping block: Mac OS Extended plus encryption, also known as encrypted HFS+.
Which Mac volumes actually fall into Apple’s macOS 28 cutoff?
The affected volumes are those that show both “Mac OS Extended” and “Encrypted” in Disk Utility. Apple gives this example:
“CoreStorage Logical Volume • Mac OS Extended (Case-sensitive, Journaled, Encrypted)”
Those volumes will not be compatible with macOS 28 and later unless users act first.
The distinction matters because Apple is not dropping all Mac OS Extended support. The company says unencrypted Mac OS Extended volumes will continue to be supported in macOS 28 and later. APFS volumes are not the target of this notice. Nor does Apple’s support page describe non-Mac formats as affected.
| Volume type | macOS 28 status based on Apple’s notice | User action |
|---|---|---|
| Encrypted Mac OS Extended / HFS+ | Not compatible | Decrypt or reformat |
| Unencrypted Mac OS Extended / HFS+ | Still supported | No required change stated |
| APFS / APFS (Encrypted) | Apple’s recommended reformat target | Use for future compatibility |
| Other formats | Not addressed by this Apple notice | Check separately |
Apple says Macs may begin warning users in macOS 26 when they connect an encrypted Mac OS Extended disk that will not work with macOS 28 or later. The warning will identify the volume by name.
That early-warning window is the useful part. It gives users time to inspect drives before the upgrade creates a practical access problem.
What choices do users have before upgrading?
Apple gives two paths: reformat or decrypt.
Reformatting is cleaner, but destructive. Apple says users can erase and reformat the volume as APFS or APFS (Encrypted). That “permanently deletes all data on the volume,” so the safe version of this workflow starts with a verified backup, not a quick click through Disk Utility.
Decrypting preserves the existing volume structure, but it is not instant. Apple says users should connect the drive, unlock it with the encryption password, Control-click the drive in Finder or on the desktop, choose Decrypt, enter the password again, then wait. The company warns that decryption “takes time, especially for large volumes.”
There is also a major carveout: Apple says the decrypt option doesn’t apply to encrypted Time Machine backup disks.
After decryption, Apple says users can optionally convert the volume to APFS without erasing it by using Disk Utility’s Convert to APFS command. If they want encryption afterward, they can encrypt the APFS volume again from Finder.
Why does APFS make encrypted HFS+ easier for Apple to leave behind?
Apple does not give a reason for the cutoff. That absence is important. The support document explains the rule and the migration paths, not the internal technical rationale.
Still, the direction is clear. APFS replaced Mac OS Extended as the default Mac file system in macOS High Sierra, which launched in 2017, according to the supplied reporting. By the time macOS 28 arrives, APFS will have been Apple’s default Mac file-system standard for roughly a decade.
MLXIO analysis: Apple is not killing HFS+ outright. It is narrowing the legacy surface area to unencrypted HFS+ volumes while steering encrypted storage toward APFS. That is a more surgical move than a total cutoff, but it still forces action from users who treated encrypted HFS+ as permanent cold storage.
The hard part is not identifying Apple’s preferred destination. It is moving the data without losing context, access, or confidence.
For users tracking Apple’s broader Mac maintenance cadence, this storage warning sits alongside practical platform housekeeping covered in No New Features: macOS 26.5.2 Quietly Patches Macs. For security-focused readers, AirDrop Vulnerabilities Let Strangers Crash Apple Features is a useful parallel reminder that Apple platform risk often shows up in specific subsystems, not just headline features.
Who feels this change first: admins, archivists, or everyday Mac users?
MLXIO analysis: The most exposed users are not necessarily the most technical ones. They are the ones with the oldest storage habits.
Enterprise Mac administrators may welcome a smaller compatibility matrix, but they now need an inventory problem solved before macOS 28 lands. Which attached drives are encrypted HFS+? Which users have old external disks? Which workflows still require them?
Archivists, researchers, legal teams, and anyone managing preserved records have a different concern. Decrypting or reformatting can raise questions about chain of custody, metadata handling, and long-term readability. Apple’s document tells users how to keep access. It does not address preservation policy.
Creative professionals may discover the issue later. A decade-old client project drive can sit untouched until a revision request arrives. If that disk is encrypted HFS+, macOS 28 becomes the point where “old but readable” turns into “needs migration first.”
Everyday Mac users face a simpler risk: confusion. Many people know they encrypted a drive. Far fewer know whether it was formatted as HFS+, APFS, or something else. Apple’s macOS 26 warning should help, but only if users connect the relevant drives before macOS 28.
How should users audit drives before macOS 28 arrives?
Start with Disk Utility. Apple says users should open Disk Utility, choose Show Only Volumes from the View menu, select the volume, and look directly under the volume name. If it says both Mac OS Extended and Encrypted, that volume is in the danger zone.
A safer migration workflow looks like this:
- Inventory: Connect old external drives and identify any encrypted Mac OS Extended volumes.
- Prioritize: Start with irreplaceable archives and active project drives.
- Back up: Make a second copy before erasing, converting, or decrypting.
- Migrate: Reformat as APFS/APFS (Encrypted), or decrypt first and optionally convert to APFS.
- Verify: Open files, check folder structures, and confirm the data is usable before retiring the old setup.
The biggest mistake is waiting until after macOS 28 is installed. Apple’s notice is not dramatic because it offers time. It becomes disruptive only if users ignore the warning period.
What evidence will show whether this becomes a smooth APFS migration or a support headache?
The first signal will arrive with macOS 26. Apple says Macs might notify users when they are using an encrypted Mac OS Extended disk that will not be compatible with macOS 28 or later. If those warnings are clear, frequent enough, and tied to the right volume names, many users can fix the issue before it matters.
The second signal is user behavior. If people connect old drives before upgrading, this becomes a manageable cleanup. If the affected disks stay offline until after macOS 28, the problem shifts from file-system policy to surprise data-access failure.
The strategic takeaway is narrow but important: file systems are no longer permanent background infrastructure. On the Mac, they are lifecycle-managed technology. Encrypted HFS+ had a long runway after APFS became the default in 2017. Apple is now marking the end of that runway.
Key Takeaways
- Encrypted HFS+ drives will stop working as supported volumes in macOS 28 and later.
- Users with archived or external encrypted Mac OS Extended disks need to decrypt or reformat them before upgrading.
- Unencrypted Mac OS Extended and APFS volumes are not the target of Apple’s cutoff.
