My Mac drive with an HFS partition stopped mounting, and I realized I don’t have a backup. I’m trying to figure out whether HFS data recovery software or a professional recovery service is worth attempting before I risk making the lost files harder to recover.
Deleted files on HFS or HFS+ usually aren’t gone the moment you delete them, even if you already emptied the Trash. macOS mostly just marks that part of the drive as free space. The actual file data can still be sitting there until the system writes something new over it.
So the big thing is this: stop using the drive as much as possible. Don’t copy files to it, don’t install apps on it, and don’t keep working from it if you can avoid it. The more the drive gets used, the higher the chance that the deleted files get overwritten. That matters more than which recovery app you choose.
If it’s your Mac’s internal drive and you can’t fully stop using the machine, at least keep activity to a minimum and install any recovery software somewhere else.
It’s definitely worth trying recovery software if the drive still appears in Disk Utility and the problem is normal deletion, an emptied Trash, accidental formatting, or a drive acting flaky but still readable. If the drive is making clicking sounds, won’t spin up, or doesn’t show up at all, that’s a different situation and probably needs a recovery lab.
For a straightforward attempt, Disk Drill is one of the easier options because it has a normal visual interface and lets you scan and preview recoverable files before paying.
The basic process is:
1. Install Disk Drill somewhere other than the drive you’re recovering.
If the lost files are on the internal Mac drive, install Disk Drill on an external USB drive or another external disk. If you’re recovering an external drive, install Disk Drill on the Mac itself. Don’t install recovery software onto the same drive you’re trying to save.
2. Open Disk Drill and choose the problem drive.
It should show you the connected drives. Pick the one that had the missing files.
3. Start the scan with “Search for lost data.”
Large drives can take a while. You can review found items before the scan finishes, but letting the scan complete usually gives you the best shot.
4. Preview the results.
After the scan, Disk Drill groups files by type, like photos, documents, and videos. Use the preview icon to check whether the files are actually intact before recovering them.
5. Select the files and recover them.
Check the files you want back, then click Recover.
6. Save them to a different drive.
This part is important. Don’t recover files back onto the drive you just scanned. Use another disk or another safe location, otherwise you risk overwriting the same data you’re trying to restore.
One small upside with older Macs using HFS+ is journaling. The file system keeps a record of recent changes, and recovery tools can sometimes use that to bring back original filenames and folder paths, not just raw file data. But that journal gets updated over time, so waiting and continuing to use the drive can make recovery messier.
If Disk Drill’s free scan shows your files and the previews look good, that’s a strong sign the data is still recoverable. At that point, the main job is getting it copied off the risky drive without writing anything new to it.
Expect the first attempt to be imperfect, especially if the partition stopped mounting rather than files just being deleted. I agree with @mikeappsreviewer about not writing to the drive, but I’d go one step earlier: if the drive still shows up at all, make a sector-by-sector image or clone to another disk first, then scan the clone with Disk Drill or whatever recovery tool you choose. Scanning the original can stress a weak drive for hours, and if it’s getting worse, that may be your only readable pass. If the data is replaceable, software is worth trying. If it’s business records, family photos, or anything you’d pay real money to get back, don’t keep experimenting on the original drive. That’s when a recovery service starts making more sense.
A drive that won’t mount because the HFS catalog is scrambled is a different case from a drive that is clicking, disappearing, or taking forever to show up. In the first case, recovery software can be worth a shot. In the second, every scan is basically another long workout for a drive that may already be failing.
I agree with @kakeru on cloning first, but I’d be even more cautious about the “repair” buttons. Don’t run Disk Utility First Aid, fsck, or any tool that promises to rebuild the volume until you’ve copied the disk or decided the data is not worth paying for. Those tools can make changes to the file system, and if they guess wrong, recovery can get worse instead of better.
Disk Drill or a similar app is reasonable if the drive is stable enough to image or scan and you are okay with imperfect results. Expect missing folder names, duplicate-looking files, weird filenames, and some files that preview fine while others are junk. If the files are irreplaceable, the better move is boring but safer: power it down, stop testing, and get a quote from a recovery lab. If the value of the data is lower than the lab bill, clone it and experiment on the clone. That’s the line I’d use.
If that HFS volume was encrypted, recovery software is a lot less magical than people expect. It may see a partition or a pile of sectors, but it won’t turn encrypted data into usable files unless the volume can be unlocked with the right password or recovery key first. Same goes for a recovery shop, by the way. They can sometimes get a dying drive readable, but they still need the credentials if the data itself is encrypted.
I’d check that before spending money on apps. In Disk Utility, Terminal, or even another Mac, see whether the disk is showing as an HFS/HFS+ volume, a CoreStorage/FileVault volume, or just an unreadable device. If it is asking for a password and then failing to mount, that is a different problem from “the directory tree is damaged.” If it never asks for a password and only shows the physical disk, then you’re more in the territory the others are talking about: image first if possible, then scan.
Disk Drill is worth a try when the drive is stable and you can preview real files, but I would not treat the scan result list as proof until previews open correctly. Recovery tools often show old filenames, partial files, or files that technically exist but are not usable. Photos and PDFs are easy to sanity-check. Mail libraries, Photos libraries, virtual machines, and big project folders are more annoying because “recovered” may still mean broken.
The cheap path is: don’t write to the disk, confirm whether encryption is involved, make an image if the disk stays connected, then test recovery on that image. The expensive path is: stop powering it up and ask a lab. The wrong path is paying for software because it shows a huge number of “found files” before you know whether the drive is readable, unlocked, and producing usable previews.