Q: iPhone won't sync after iTunes 12.2 update

What have you already done to try to solve the problem?

Launch the Console application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad and start typing the name.

The title of the Console window should be All Messages. If it isn't, select

          SYSTEM LOG QUERIES ▹ All Messages

from the log list on the left. If you don't see that list, select

          View ▹ Show Log List

from the menu bar at the top of the screen.

Click the Clear Display icon in the toolbar. Then take an action that isn't working the way you expect. Select any lines that appear in the Console window. Copy them to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.

The log contains a vast amount of information, almost all of which is irrelevant to solving any particular problem. When posting a log extract, be selective. A few dozen lines are almost always more than enough.

Please don't indiscriminately dump thousands of lines from the log into this discussion.

Please don't post screenshots of log messages—post the text.

Some private information, such as your name or email address, may appear in the log. Anonymize before posting.

When you post the log extract, you might see an error message on the web page: "You have included content in your post that is not permitted," or "The message contains invalid characters." That's a bug in the forum software. Please post the text on Pastebin, then post a link here to the page you created.

Are you signed in to the same iCloud account on the phone that you use on the Mac? Do you use iCloud keychain?

Please take these steps to resynchronize the iCloud keychain. Your keychain on iCloud and your other Apple devices won't be affected. Take Step 2 only if Step 1 doesn't solve the problem.

Step 1

Back up all data.

Open the iCloud preference pane and uncheck the Keychain box. You'll be prompted to delete the local iCloud keychain. Confirm—the data will remain on the servers. Then re-check the box. Follow one of the procedures described in this support article to set up iCloud Keychain on an additional device. Test.

Step 2

If you still have problems, uncheck the Keychain box again and continue.

Triple-click the line below on this page to select it, then copy the text to the Clipboard by pressing the key combination  command-C:

~/Library/Keychains

In the Finder, select

          Go ▹ Go to Folder...

from the menu bar and paste into the box that opens by pressing command-V. You won't see what you pasted because a line break is included. Press return.

A folder named "Keychains" should open. Inside it is a subfolder with a long name similar to (but not the same as) this:

           421DE5CA-D745-3AC1-91B0-CE5FC0ABA128

The above is only an example; yours will have a different name of the same general form. Drag the subfolder (not the Keychains folder) to the Trash and empty.

Restart the computer and re-enable iCloud Keychain.

I don't think you can solve this problem on your own. It involves the state of your account on Apple's network. Click the Support link at the top of this page to schedule a call from Apple Support.

Please update this thread with the outcome of the support call so others can benefit from your experience.