Mac Field Guide

TroubleshootingFix

Can't update your Mac? Fixes for macOS updates that won't download, install or finish

Applies to macOS 26 Tahoe · macOS 27 Golden GateReviewed 2 November 2026Tested on macOS 27.2 and Tahoe 26.6.22 min read

Short answer

Most failed updates come down to four things: the Mac isn't compatible, there isn't enough free space, the download was interrupted, or the Mac went to sleep. Check compatibility first, free up storage, keep the Mac plugged in and awake, and restart before trying again. If it still fails, download the full installer from Terminal.

On this page
  1. The update doesn't appear
  2. The download fails or stalls
  3. Stuck on "Preparing" or a progress bar that doesn't move
  4. Download the full installer
  5. Last resort: reinstall from Recovery
  6. Sources and further reading

The update doesn't appear

  • Is your Mac compatible? macOS 27 needs Apple silicon. See the compatibility list.
  • Is the Mac managed by work or school? Look in System Settings › General › Device Management. Your IT team may be holding the update back.
  • Beta updates. In System Settings › General › Software Update, click the ⓘ next to Beta Updates and set it to Off if you don't want betas.
  • Restart and check again. On macOS 27, some people saw updates fail to appear while Rosetta was installed until they restarted.
Software Update settings
macOS 27.2: Software Update in General.

The download fails or stalls

  1. Free up space. Open System Settings › General › Storage and use the recommendations. Leave well over 20 GB free for a major update.
  2. Check Apple's System Status page for a problem with macOS Software Update.
  3. Turn off VPNs, proxies and content filters, or use a wired connection.
  4. Plug in the charger and keep the lid open, because downloads pause when the Mac sleeps.
  5. Restart, delete any half-downloaded Install macOS app from Applications, and try again.

Stuck on "Preparing" or a progress bar that doesn't move

Give it time, ideally overnight: the estimate is often wrong. If nothing has changed for several hours, hold the power button until the Mac turns off, turn it back on, and try again. Starting once in Safe Mode, then restarting normally, can also clear a stuck update.

Download the full installer

This gets the whole installer instead of an incremental update, which avoids many failures. List the available versions:

softwareupdate --list-full-installers

Download the newest one:

softwareupdate --fetch-full-installer

Then open the Install macOS app from your Applications folder.

Last resort: reinstall from Recovery

Back up first. Start up in Recovery (on Apple silicon, hold the power button until you see startup options, then choose Options), choose Reinstall macOS, and don't choose to erase anything. Reinstalling keeps your apps and files. Afterwards, run Software Update again to get the newest version.

Sources and further reading

Applies tomacOS 27Tahoe

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