To retrieve your existing iOS Distribution Certificate P12 file:
Note: You must use the Mac computer on which the original P12 file was generated.
- Click the magnifying-glass icon at the top-right corner of your screen.
- Type Keychain Access into the Spotlight search bar.
- Click Keychain Access.
- Click My Certificates under Category on the left side of the screen.
The certificates stored on your computer are displayed in the panel.
- Right-click the relevant iPhone Distribution file, and click "Export "iPhone Distribution:...".
- Before you can save the iOS Distribution certificate file to your computer you are prompted to enter a password for the file.
- Create a password, and then re-enter the password to verify it.
- Click OK.