How do I stop Keychain from popping up all the time? OSX mountain lion

Hi. I had same problem. This helped me. Don't forget to restart at the end. You will be prompted for login once more when you log back in but as long as you check the box 'save in my key chain" you should be ok

Hope it helps

http://support.apple.com/kb/TS1544

Insert your old keychain password when prompted so it can sync with your new account password.