Fixing iCloud “Unknown error occurred” & “Mac can’t connect to iCloud because of a problem” Errors
Some Mac users may encounter an error message stating “This Mac can’t connect to iCloud because of a problem with firstname.lastname@example.org”, which then directs the user to open the iCloud preferences. Once inside Mac iCloud preference panel, some users may be able to successfully login to iCloud, but often another error is encountered here which states “An unknown error occurred” when trying to login to iCloud on the Mac, or sometimes the iCloud preference panel freezes up and spins endlessly. Once these two error messages have been encountered, the Mac will typically be stuck in an infinite loop of iCloud login failures with an endless unknown error and the endless “problem” pop-up message, which prevents all iCloud functionality from working on the Mac including Messages, FaceTime, Notes, Mail, Contacts, Calendars, and all other iCloud related abilities.
This set of iCloud unknown errors and problems is not exactly rare (see 1, 2, 3) and can be notoriously quirky to resolve, but the steps below should remedy these type of iCloud login issues on a Mac if they are seen.
How to Fix “This Mac can’t connect to iCloud” and Unknown Errors with iCloud on Mac
This is a multi-part series of troubleshooting steps that will resolve most iCloud connection issues on Mac.
Check if iCloud is Down or Not
If iCloud is down, you will need to wait until it is back up again before being able to resolve the issue.
Quick side note: if iCloud was down but is now back up, there may be a lingering connectivity issue due to caching or otherwise, in that case proceed with the steps below and you can likely resolve the connection difficulty.
Quit All iCloud Apps, Reboot the Mac
Next up is to quit out of every app that is using iCloud, this includes quitting Messages, quitting FaceTime, Calendar, Notes, Reminders, etc. Be sure to quit the System Preference app as well. If the apps are stuck or not responding, go ahead and use Force Quit on the apps to exit them.
Once all of those apps have been quit, go ahead and restart the Mac as usual by going to the Apple menu and choosing “Restart”. If the Mac is frozen or refusing to reboot, you can do a forced reboot as well.
When the Mac boots back up again as usual, don’t open any iCloud apps yet, instead first go to the iCloud Preference panel ( Apple menu > System Preferences > iCloud) and attempt to login to the Apple ID / iCloud account again. At this point the iCloud login should proceed as usual, in which case using Messages and FaceTime should work without incident.
Removing iCloud Configuration Files
This is unverified but some users in our comments report it can work to resolve iCloud connection issues in Mac OS. Be sure you backup your Mac before attempting this procedure:
- From the Finder, choose the “Go” menu and select “Go To Folder” and then enter the following path:
- Copy the files found in this location to the desktop or elsewhere that can be easily recovered if desired
- Remove the files from the ~/Library/Application Support/iCloud/Accounts/ folder so that it is empty
- Reboot the Mac
You will likely need to re-login to iCloud when the Mac reboots. You can also log out and back into iCloud if things are still not functioning correctly to regenerate new Account data files.
Log out and Back in to iCloud
If you know iCloud is online, you quit all iCloud apps and rebooted, and you are still having difficulties, you’ll want to log out of iCloud, reboot, and then log back in.
Go to the Apple menu and open System Preferences, then choose iCloud. Select to “Sign Out”.
Reboot the Mac as usual.
Once the Mac has booted back up again, return to the iCloud preference panel, and login to the Apple ID as usual.
Removing Keychain Data, Rebooting
If you use iCloud Keychain, then you may find that removing local keychain data can resolve this issue.
- From Finder, select the “Go” menu and choose “Go To Folder”, and then enter the following path:
- Copy all files found in this user Keychains folder to the desktop, or to a backup folder called “Keychains backup” so that you can restore these files manually easily if you need to
- Now remove all files from ~/Library/Keychains/ so this folder is empty
- Restart the Mac
The iCloud errors should now be gone, and the Keychains data should recover itself from iCloud Keychain.
Note if you simply trash these files without having a backup of them, and without using iCloud Keychain, you will lose your keychains data, which is not a desirable outcome. Thus it’s important to backup the keychain files before trying this trick out.
This particular trick was left in our comments by Gunnar and confirmed by several others to have resolved the problem for them.
That should be enough to fix the iCloud “Unknown error occurred” problem and the pop-up message stating the Mac can’t connect to iCloud because of a problem with the Apple ID.
Did a particular method work to resolve the unknown iCloud error for you? Do you have another solution? Let us know in the comments.