

After you enter your new password (same to the password of your Mac account), Keychain Access creates an empty login keychain with no password. Choose Preferences from the Keychain Access menu (or Cmd ,), then click the Reset My Default Keychain button in the preferences window.Open Keychain Access, which is in the Utilities folder of your Applications folder.

Please note: you'll lose all your passwords stored in it. To solve this problem, you have to reset your default keychain. Changing login keychain's password does not help. On macOS El Capitan and Sierra, there is no Keychain Access > Keychain First Aid. It should be caused by changing Mac password using 3rd party software. It has bothered me for several weeks on my new Mac. Because of this, you will be prompted to enter a keychain password each time an application requires authentication that your keychain would normally provide. If you change your account's password using your Mac OS X Install disc (or if your network-based account password is changed due to a network admin forcing a password change), your default keychain password (which uses the same initial password as your user account) does not change. This is needed because, as Apple explains it: Re-enter the newer password in the Verify field, then click OK.In the New Password field, type the password that matches your current account password.If you entered the correct password, a new window appears enter the original password again in the Current Password field.

