macOS Update Stuck or Won't Install? Free Space, Safe Mode and Install from Recovery

Published ✓ Verified ⏱️ 2 min read May 15, 2025 · by Ryan Bennett

A macOS update or upgrade won’t finish — it errors out, stalls, says it can’t be verified, or warns that there isn’t enough storage space to install.

Why: The most common causes are too little free disk space, another app or installer interfering, a damaged downloaded installer, or disk errors. Apple’s guidance is to clear those one at a time, and the cleanest fix is to install macOS from Recovery, where no other software can get in the way.

Fix 1: Free up space and check your connection

If the message says your Mac doesn’t have enough storage, free up space before retrying — see free space when the startup disk is full.
Make sure your Mac is connected to the internet; the installer downloads files as it runs.
Restart and try the update again from Apple menu > System Settings > General > Software Update.

Fix 2: Try safe mode, then update

If you’re installing through Software Update or the App Store, starting in safe mode first can clear interfering software and caches.

Apple silicon (M-series): Shut down, press and hold the power button until “Loading startup options” appears, select your disk, then hold Shift and click Continue in Safe Mode.
Intel: Turn on or restart, then immediately press and hold Shift until the login window appears.

You’ll see Safe Boot in the menu bar. Run Software Update again, then restart normally to leave safe mode.

Fix 3: Install macOS from Recovery

Installing from Recovery stops other software from interfering and is Apple’s recommended route for a stubborn update.

Apple silicon: Shut down, then press and hold the power button until “Loading startup options” appears, click Options, then Continue.
Intel: Turn on and immediately press and hold Command (⌘)-R.

In Recovery, first open Disk Utility and run First Aid on your startup disk, then quit Disk Utility, choose Reinstall macOS, and follow the prompts. This keeps your data.

Fix 4: Delete a damaged installer

If your Mac says a previously downloaded installer is damaged or can’t be verified, delete that installer, repair the disk (Fix 3), then download a fresh copy from Apple via Software Update or the App Store.

FAQ

It says “not enough space” but I think there’s plenty. macOS needs free working space beyond the download itself. Free several GB (Fix 1) and retry; starting in safe mode also clears system caches to recover space temporarily.

Nothing works — can I reset? As a last resort you can erase your Mac and reset it to factory settings, which will reinstall macOS. Back up first.

Sources: Apple Support — If an error occurred while updating or installing macOS · Apple Support — Start up your Mac in safe mode