How to cope better with problems which can occur with iCloud Keychains, and how to make your own local backups.
Keychain Access
Authentication dialogs to permit access to your keychain are supplied by the macOS security system, and follow a strict pattern.
This new version adds a Help Book, Tooltips, and supports window resizing more usefully.
This may help you work out what is going wrong with local keychains in Sierra. Another free tool to spare you from Terminal.
Sometimes resorting to Terminal can be the best and simplest way to fix a keychain problem.
OS X used to provide a keychain first aid feature. Now this has gone, this is the only way that you can try to repair a defective keychain: create a new one.
Sierra sticks with the old favourites like Disk Utility, but still can’t repair permissions or keychains. A new app, Storage Management, has been added.
Late last year, the utility for repairing keychains quietly vanished from macOS 10.11.2. No one seems to know where its functionality went.
Why do I have to enter my keychain password every time my Mac starts or restarts?
Can I change password entry dialogs to show the correct characters instead of blobs?
The Eclectic Light Company 