Why App Settings Reset After Every Restart on macOS 27

You turn off an app’s annoying notifications, but they’re back on after restarting your Mac. You change the setting again, but it works until the next restart.

If the issue appeared after upgrading to macOS 27, the update is an obvious suspect. But the timing alone doesn’t explain everything. Let’s narrow the problem down before you try resetting anything.

Did the Problem Start After the Upgrade?

The upgrade gives you a clear point in time to work from. If an app kept your preferences before you installed macOS 27, check for compatibility notes or updates published by its developer. For a broader look at other reported post-upgrade issues, this source gives useful details. Compare the reports with what you’re seeing on your Mac. Pay attention to the affected apps and software versions.

It’s also important to check which macOS versions those reports concern. A problem reported during an early beta has probably been fixed before the public release. Note your installed macOS version, the app version, and when you first noticed the reset. With these details, you can compare your experience with relevant reports and explain the issue if you contact support.

When Does the Setting Reset?

Start the easy way: test if the preference disappears when you reopen the app or only after restarting your Mac.

Start with a preference that’s easy to check, like the app’s color theme. Change it and click Save. Then quit using the app’s menu or Command–Q. It’s important to do it that way, since closing its window can leave the app running.

Open it to check the preference. If you still see the old theme, the problem is there without restarting the computer. If the change stays, restart the Mac as you usually do and check once again.

Update the App and Check What Controls Its Settings

Now that you know when the preference resets, do this:

Check Compatibility and Updates

Look at the developer’s support page or release notes for macOS 27 compatibility. Even if an older copy of the app still runs fine on your computer, it may not be the version its developer adapted for this particular system. In fact, a missed update is the most common cause for app misbehavior.

Update the app and test your setting again. Check for macOS updates in System Settings > General > Software Update, too. Test after each update, so you can tell if it affected the app’s behavior.

Look for Sync Conflicts or Managed Settings

Does the app sync preferences through an online account? Check if the same setting is different on another device. If your change stays at first but reverts after syncing, that gives us something to investigate. Follow the developer’s instructions for testing preference sync without removing your data.

On a work-managed Mac, settings may be controlled by the organization. If an option is locked or keeps returning to a required value, you can contact IT to ask if a policy controls it. Repeatedly changing a managed setting won’t resolve underlying restrictions.

Before Resetting Preferences, Back Them Up

The updates and sync checks didn’t help, so what’s next? The app’s saved preferences! The issue may involve a damaged preference file, or maybe the app lacks permission to write changes to its storage folder.

Before trying a reset, it’s important to back things up with Time Machine. That gives you a way to recover files if you remove the wrong one. Also, export the app’s settings if it offers that option, or take screenshots of the preferences you want to restore.

Then, follow the developer’s instructions for resetting that specific app. The locations of preferences vary, so avoid deleting files simply because they seem to have relevant names. Quit the app before making any changes, and keep a copy of the identified files.

Test in a Separate Mac User Account

If the setting still resets, you can try how the app behaves in a temporary user account. This way, you can test it without the preferences and account setup you normally use.

• Open System Settings > Users & Groups
• Click Add User to create a standard account
• You’ll need administrator approval on the Mac

Log into the new account and open the app. Where possible, leave cloud preference sync disconnected, so it doesn’t bring your existing settings into the test.

Change the same preferences, quit and reopen the app. Then, restart the Mac. Does the change stay? If that’s the case, focus on the app’s preference files, their permissions, and any preference sync enabled in your usual account. If it resets in both accounts, contact the developer to investigate an app fault.

Still Losing Your Settings?

At this point, you have enough detail to ask support for help. Tell them exactly which setting changes back and when it happens. Include your app and macOS versions in the message, so they can try to reproduce it.

Last Updated on 6 October 2026 by tfk the5krunner

theparkrunner

theparkrunner is a contributing writer covering road races, endurance events and the travel side of racing life. Reports focus on upcoming events, race destinations and what athletes need to know before they arrive.