Keychain password change

Question

I think my girlfriend changed my password to keychain access. it used to be the same as my login. now mail, safari, etc. apps ask for a keychain password but when i use my login password it says invalid. How can i change my keychain password back?

Answer 1

You can try this:
Tutorial: Keychain issues; resolving
If you can't access your keychain, or forget your password If you can't get into your keychain file because you've forgotten your password or the keychain file appears to be corrupt, there are a couple of options.
First, if you've forgotten your password, you can use the "Keychain First Aid" utility to make the keychain password the same as the login password.
This can be accomplished via the following process:
Open Keychain Access (located in Applications/Utilities
Go to the "Keychain Access" menu and select "Preferences"
Click the "First Aid" tab
Make sure the "Synchronize login keychain password" box is checked
Close the Preferences window
Go to the "Keychain Access" menu and select "Keychain First Aid"
Enter your username and password
Click the "Repair" button
Another option is to completely delete your keychain then recreate it. This routine is useful if your keychain appears to be corrupt or otherwise inaccessible.
This can be accomplished as follows:
Launch Keychain Access (located in Applications/Utilities)
Click "Show Keychains" in the lower-left corner of the window.
Select the problematic keychain from the left-hand pane.
Navigate to the "File" menu and select "Delete Keychain '(name of keychain)'"
Check all options for deletion and press "OK"
Create a new keychain by going to the "File" menu, then "New" and selecting "New Keychain"
You can now make this keychain your default if you desire by selecting it, then going to the "File" menu and selecting "Make '(name of keychain)' Default"
Login as root and perform repair In some cases, problems with keychains can only be resolved when logged in as the root user.
First, enable root user.
After enabling the root user, and logging in under this account, again open Keychain Access. First attempt repairs using Keychain First Aid, and failing that, delete then recreate the keychain as described above while logged in as root.
Persistently asked for stored passwords If you are persistently asked for passwords in various applications that you have specified should be remembered in a keychain, your "login" keychain may not be active for one reason or another.
Navigate to ~/Library/Keychains/ (this is the Library folder inside your user home folder). Find the file named "login.keychain" and double-click it.
Failing that, select the "login" keychain within the Keychain Access application and make sure it is the default keychain by going to the "File" menu and selecting "Make 'Login' Default"
Turn off Keychain synchronization in applications having problems If specific applications are experiencing issues when accessing password-protected material, Keychain may be to blame.
For example, it appears that in some cases, failures in .Mac synchronization transfers are linked to issues with Keychain.
If you are having problems synchronizing data with .Mac servers, you may want to try the following process:
Open System Preferences and access the .Mac pane
Click the "Sync" tab
Uncheck the "Synchronize with .Mac" checkbox
Close System Preferences
Re-open System Preferences and repeat steps 1 and 2
Re-check the "Synchronize with .Mac" checkbox
If the above process does not re-allow synchronization, you may need to leave Keychain synchronization turned off in the "Sync" tab of the .Mac System Preferences pane.
The above comes from an article published on MacFixit.com.