Auto-Unlock Keychain at Startup in Mac OS 9

In classic Mac OS 9, entering a password every time you boot to access saved server credentials, email accounts, and web passwords can become repetitive. Users can bypass manual entry and automatically unlock their keychain at system startup either by synchronizing the keychain with the Multiple Users login feature, setting an empty keychain password, or utilizing a simple AppleScript placed inside the Startup Items folder.

Method 1: Synchronize with the Multiple Users Feature

The standard way Apple designed keychains to unlock automatically upon startup in Mac OS 9 is through integration with the Multiple Users control panel.

  1. Open the Apple Menu, select Control Panels, and open Multiple Users.
  2. If Multiple Users is not turned on, click the toggle to turn it on and set up your user account.
  3. Open the Keychain Access control panel.
  4. Select your keychain from the list and navigate to Edit > [Keychain Name] Settings (or click the Change Password button).
  5. Change the keychain password to match your Mac OS 9 user account login password exactly.
  6. When your Mac boots and you log into your user account, the operating system will use your login credentials to unlock your keychain in the background.

Method 2: Set a Blank Keychain Password

If you do not use the Multiple Users feature and boot directly to the desktop, you can prevent password prompts entirely by removing the password requirement.

  1. Open the Apple Menu, select Control Panels, and open Keychain Access.
  2. Select your default keychain and go to Edit > [Keychain Name] Settings.
  3. Choose the option to Change Password.
  4. Enter your current password in the designated field.
  5. Leave the New Password and Verify fields completely empty.
  6. Click OK and confirm when warned about security implications.

Because the keychain requires no password to open, any application requesting stored credentials will access the keychain automatically at startup without a prompt.

Method 3: Use an AppleScript in the Startup Items Folder

If you prefer to maintain a strong password on your keychain but do not use the Multiple Users environment, an automated script can enter the credentials at boot.

  1. Open the Script Editor utility, typically found in Applications/Apple Extras/AppleScript.
  2. Enter the following script: 
    tell application "Keychain Scripting"
    unlock current keychain with password "YourPasswordHere"
end tell
  3. Replace "YourPasswordHere" with your actual keychain password.
  4. Go to File > Save As, name the file (e.g., "Unlock Keychain"), set the format to Application, and leave "Stay Open" unchecked.
  5. Open your system hard drive, navigate to the System Folder, and locate the Startup Items folder.
  6. Drag your saved script application into the Startup Items folder.

At every system startup, Mac OS 9 will launch the script, silently unlocking your keychain for the rest of your session.