Should AddressBookScheduledSync be kept active on macOS?

After the last few system updates, a message saying that AddressBookScheduledSync is running in the background and inviting me to go in the settings to decide to manage it. Since i presume that it has to do with the sync of the contacts and it's active in the background activities, i don't worry about it and keep it active.

I read recently that it is an app that was use in MobileMe to sync the contacts.

We are at MacOS 27 and MobileMe has been replaced long ago... Does AddresBookSecdulerSync is still relevant. Can I deactivate it ?

Thanks

Posted on Nov 3, 2026 9:16 AM

2 replies

kaz-k

Level 9 (53,902 points)

Nov 3, 2026 9:56 AM in response to Gaetan Blouin

Yes, AddressBookScheduledSync (and its active process AddressBookSourceSync) should generally be kept active on macOS.

It is a legitimate, built-in system component that coordinates background syncing for your Contacts app.

Gaetan Blouin Author

Level 1 (8 points)

Nov 3, 2026 12:57 PM in response to kaz-k

Thanks !