macOS Catalina stuck on 'less than a minute remaining'

You’re upgrading to macOS Catalina. The progress bar fills up, then it shows “less than a minute remaining” — and that minute never actually ends. The spinner keeps spinning. The Mac seems to be doing something because the drive light flickers, but it doesn’t finish. You might have waited an hour, maybe even left it overnight. It’s not going to finish on its own.

What’s actually happening here

The macOS installer runs in two phases. Phase one copies the installer data to the target volume and reboots. Phase two — the one you’re stuck in — runs from that temporary macOS Recovery environment. At the very end of phase two, the installer needs to finalize the system volume and set the boot volume to the new OS. That finalization step does a lot of file system operations and must sync the system clock with Apple’s certificate services.

Two things commonly jam this step:

• Date and time mismatch. If your Mac’s clock is wrong — especially if it’s set to a date before Catalina’s certificate expiration — the installer can’t verify the signed update bundle and hangs.
• A stuck background process. During installation, macOS spawns several helper processes (like installer, osinstallersetupd, and authd). If one of these crashes silently or enters a deadlock, the progress bar never advances past that final tick.

The fix — step by step

You’re going to force the installer to finish by either restarting the stalled process or resetting the clock. I’ve done this dozens of times on Macs from 2012 to 2019. It works.

1. Wait ten real minutes first. Sometimes the “less than a minute” phase takes 5–10 minutes on slower drives (especially Fusion Drives or old spinning disks). Give it that grace period. If the drive light is still flickering irregularly, it’s working. If the light is solid on or off for 60 seconds straight, it’s stuck.
2. Open Terminal from the macOS Utilities menu. At the top of the screen, you’ll see “Utilities” in the menu bar. Click it, then select “Terminal”. This gives you a bash shell running as root.
3. Check the date. Type date and hit enter. If it shows anything other than today’s date — for example, January 1, 2001 or a date in 2019 — that’s your culprit. The macOS installer uses the date to verify the installer’s digital signatures.
4. Fix the date. Use the date command to set it to the current time. For example: date 042710452025.00 sets it to April 27, 2025 at 10:45 AM. The format is mmddHHMMYYYY.ss. You can also run ntpdate time.apple.com if that binary exists (it often doesn’t in the recovery environment). If you’re not sure of the exact syntax, just do date "+%m%d%H%M%Y.%S" to see the current system format, then manually type the correct values.
5. Kill the stuck installer process. Type ps aux | grep -i installer and look for the process that has the most CPU or has been running the longest. Its PID is the first number on that line. Then run kill -9 [PID]. Don’t worry — this doesn’t undo your installation. It forces the installer to die, which triggers the finalization routine to restart.
6. Reboot the Mac. Type reboot or shutdown -r now. On some Macs, you’ll need to hold the power button for 10 seconds to force a shutdown, then press it again to boot. If the installer was nearly complete, macOS will detect the partially installed system and finish the setup automatically on boot.
7. If it still hangs after reboot, boot back into Recovery (hold Command+R at startup) and do two things: run First Aid on your startup volume from Disk Utility, then re-run the macOS installer. The First Aid step repairs any filesystem inconsistencies that might block the final write.

What to check if it still fails

If you’re still stuck after the steps above, the problem is almost always one of these:

• Third-party kernel extensions. Catalina hates old kexts. If you had something like NTFS-3G, older Adobe drivers, or hackintosh fixes, boot into Safe Mode (hold Shift at boot) and delete them from /Library/Extensions/. Then try the upgrade again.
• FileVault encryption in progress. If FileVault was on and not fully encrypted (or decrypted), the installer can’t finalize the sealed system volume. Turn FileVault off before upgrading, or wait until encryption finishes.
• Not enough free space. The installer needs at least 20 GB free for the full upgrade. Check if you’re close to the edge. Catalina creates a temporary snapshot of the system volume that doubles the disk usage during installation.
• A failing drive. If First Aid reports “Invalid volume free block count” or “Incorrect number of extents,” your drive is dying. Replace it before upgrading.

One last thing: I’ve seen this exact hang on MacBook Airs from 2013–2015 more than any other model. Those have slower SATA SSDs that just take a while for the final fsck. If you’re on one of those, the fix is genuinely just patience plus the date reset. Don’t nuke the drive unless you’ve tried every step here first.