There are several possible causes for this issue. Please take each of the following steps that you haven't already tried, testing after each one, until it's resolved.
Back up all data before making any changes.
Step 1
Follow the directions in this support article.
Step 2
Open the
iCloud preference pane and uncheck the
Keychain box. You'll be prompted to delete the local iCloud keychain. Confirm. Then re-check the box. Follow one of the procedures described in
this support article to set up iCloud Keychain on an additional device.
Step 3
Open the Keychains folder as in Step 1. There should be a file in that folder with the name "login.keychain". If there is also a file iwith the name "login_renamed_1.keychain", then please do as follows:
- Rename login.keychain to "login-old.keychain".
- Rename login_renamed_1.keychain to "login.keychain".
You can then close the folder.
Launch the Keychain Access 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. Click Utilities, then Keychain Access in the icon grid.
Delete the login keychain from the keychain list. Choose
Delete References when prompted,
not
Delete References & Files.
Select
from the menu bar. Add back the file now named "login.keychain". If any of your needed keychain items are missing from it, also add back the file now named "login-old.keychain". I suggest you transfer any needed items from that keychain to the login keychain, then delete it. The transfers are made by drag-and-drop in Keychain Access. You'll need to enter your password for each item transferred.
Select
Keychain Access ▹ Keychain First Aid
from the menu bar and repair the keychain. Quit Keychain Access.