How to Reset Keychain on Mac
Did you recently lose, reset, or forget your Mac’s user password? If so, you will no longer be able to access the existing Keychain login and passwords stored on your Mac.
This is because, by default, the Keychain password is the same as your Mac user password. Since you’ve lost or reset the user password, they are no longer in sync, and you’ll need to reset your default Keychain to get them in sync again. However, doing this will remove all the passwords that are currently stored in Keychain. Therefore, reseting the keychain is a last resort and should not be taken lightly, since the inconvenience of losing all stored passwords is considerable (of course if you can’t access the keychain anyway that may not matter as much).
If you’re interested in resetting the Keychain on a Mac so that you can have the login password and keychain password match again, read on to learn how you can reset the default Keychain on a macOS machine.