An AppTesters certificate package may contain two files used together by a signing tool.

What is a .p12 file?

The .p12 file contains the signing certificate and its private key. A signing tool uses it to create a signed version of an app. The file is normally protected by a password.

Use the password supplied with your certificate package. Some legacy AppTesters packages used 123, 1, or apple.com. If the supplied password does not work, contact AppTesters support rather than uploading the file to an unknown password-checking website.

What is a .mobileprovision file?

The provisioning profile connects the signing configuration to permitted devices and capabilities. It can include the registered device UDID, application identifiers, entitlements, and an expiration date.

Both files must belong to the same certificate setup. Mixing an old .p12 with a new provisioning profile can cause signing or installation errors.

How should I protect these files?

  • Store them in a private, access-controlled location.
  • Do not share them in public chats, forums, or file repositories.
  • Do not share the .p12 password with anyone who does not need it.
  • Avoid uploading the files to unknown signing or certificate-checking services.
  • Remove obsolete copies after a replacement is working, while retaining any record AppTesters specifically asks you to keep.
  • If you believe the files were exposed, contact support and explain where they were shared.

Customers using the AppTesters In-Browser IPA Signer may not need to download these files because signing is handled within the authenticated service.