After you create signing certificates and provisioning profiles, use Accounts preferences to back up all your local developer account signing assets.
If you use automatic signing (recommended), Xcode creates signing certificates and provisioning profiles for you. However, since signing certificate private keys are stored in your keychain, you should back up the developer accounts. For example, export your developer accounts to move the signing certificates and provisioning profiles to another Mac, or to later restore a missing private key. Downloading your provisioning profiles in Xcode won’t repair a missing private key. Instead, import your developer accounts from a backup.
Note: If a private key is missing, a sheet appears in the project editor. Optionally, click Revoke to re-create the certificate.
In Accounts preferences, click and hold the Action button (the gear icon) in the lower-left corner, and choose Export Developer Accounts from the pop-up menu.
Enter a filename in the Save As field and a password in both the Password and Verify fields.
The file is encrypted and password protected.
Click Save.
The file is saved to the location you specified with a .developerprofile extension. The file contains all developer account signing certificates and provisioning profiles that are on your Mac.
In the dialog that appears, click OK.
In Accounts preferences, click the Action button (the gear icon) in the lower-left corner, and choose Import Developer Accounts from the pop-up menu.
Locate and select the file containing your developer profile, and click Open.
The file should have a .developerprofile extension.
Enter the password you used to encrypt the file, and click OK.
In the dialog that appears, click OK.