SafariBookmarksSyncAgent quit unexpectedly

Apple’s Safari web browser does some very cool stuff under the hood. One of those is that it syncs lots of data with iCloud so that you can, for example, see tabs that are open on your iPhone on your Mac or see the browsing data from all your devices in one place. One of those data is Safari bookmarks. If you have iCloud syncing turned on and you’re logged into your account, Safari synchronizes your bookmarks so that whichever device you bookmark a site on, it shows up on all your devices.

Sometimes, however, the process gets messed up, and SafariBookmarksSyncAgent quits unexpectedly. Here’s what to do when that happens.

What happens when SafariBookmarksSyncAgent quits unexpectedly?

SafariBookmarksSyncAgent is the name of the process in macOS that synchronizes your Safari bookmarks with iCloud.

When the process quits, your Safari bookmarks no longer sync. It means you may not be able to see recently added bookmarks on all your devices. So, the web pages you’ve bookmarked on your Mac may not show up on your other devices.


SafariBookmarksSyncAgent may be quitting because your Mac has been infected by malware. The easiest way to check your Mac for malware is by scanning it with a special anti-malware tool. We recommend CleanMyMac X. It can scan your Mac for malware and then remove anything it finds. And you can also set it up to protect your Mac in real-time in the background, so you don’t have to check for malware manually.

How to fix “SafariBookmarksSyncAgent quit unexpectedly” issue

Update your software

The first sign that SafariBookmarksSyncAgent has quit may be that your bookmarks no longer sync across all your devices. Here’s what to do to fix that.

  1. Check Apple’s system status page to make sure the problem isn’t at Apple’s end.
  2. Check your internet connection.
  3. Click the Apple menu and select About this Mac > Software Update to check if there are any system updates. If there are, install them.

Turn off and turn on iCloud bookmarks again

If your Mac’s already running the latest software version, there is another fix you can try: turning off iCloud bookmarks and turning them back on again.

  • Quit Safari.
  • Click on the Apple menu and choose System Preferences.
  • Select Apple ID, then iCloud. If you’re running an older version of macOS, choose the iCloud pane.
  • Uncheck the box next to Safari.
  • Quit System Preferences and wait a minute or so.
  • Launch System Preferences again and repeat steps 2 and 3.
  • Check the box next to Safari.
  • Quit System Preferences.
  • Relaunch Safari.

Bookmarks and other data should now be forced to re-sync because you had switched them off and back on again.

If none of the above work, you should try switching off Safari bookmark syncing on your iPhone or iPad and then switching it back on again in the same way you did on your Mac. To do that, launch the Settings app, tap your Apple ID, then iCloud and toggle the switch next to Safari to off. Wait for a minute or so and then toggle it back on again.

Restart your Mac entering the Safe mode

Safari agents rely on cached data within your macOS. Starting your Mac in the Safe mode rebuilds cache information which may fix the problem with SafariBookmarksSync

Reset Safari

The final option is to reset Safari, taking it back to the state it was in when you first got your Mac. The easiest way to do that is to use the Uninstaller module of CleanMyMac X (this app is notarized by Apple)

  • Launch CleanMyMac X (If you don’t have it, you can download its free edition here).
  • Click the CleanMyMac X menu and choose Preferences.
  • Select Ignore List and uncheck “Ignore system applications.”
  • Go back to CleanMyMac X.
  • Click the Uninstaller module.
  • Locate Safari and then click the dropdown arrow to the right of it.
  • Check the box next to Supporting Files and Preferences.
  • Safari reset selected in the Uninstaller module in CMMX
  • You’ll see a dropdown menu next to Safari, choose Reset.
  • Press Reset.

Now, Safari should run as good as new again.

SafariBookmarksSyncAgent is a very useful process. If you have more than one Apple device, it allows you to sync Safari bookmarks between them. However, sometimes it fails to synchronize. If that happens, the first thing to do is to check for a new software version and update your Mac.

If it’s not helping, try turning off and turning on iCloud bookmarks. Resetting Safari will revert your browser to the way it was when you bought your Mac and may fix the SafariBookmarksSyncAgent issue. Hope you managed to solve your problem!

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