invalidAppleSubscriptionKeyError (error code 17): Invalid Apple subscription key

• The backend answered 7234 (invalid Apple subscription key). The iOS SDK maps it to this error; the Android SDK maps it to unexpectedBackendResponseError (BackendErrorCode.swift, errors.kt).
• No In-App Purchase key is saved on the app, or only part of it is (key ID, issuer ID and private key).
• The private key is not a valid .p8 file, or Apple rejected it with an authorization error.
• A promotional offer was requested, and offer signing needs the key.
• When customer info fails with this error, a debug build with the SDK's failIfInvalidSubscriptionKeyDetectedInDebug flag fails loudly, and any other build falls back to offline entitlements computed on the device (CustomerInfoResponseHandler.swift).

• The SDK retries the purchase by itself once the key is right, because the server answers 5xx for a missing or broken key. Do not build a retry yourself.
• Do not show this error to customers. It is your setup problem. Alert yourself, and let customers keep using the app.
• Do not grant access from the error. Customers who paid keep access through the SDK's cached and offline entitlements.

// Swift
do {
  let result = try await Purchases.shared.purchase(package: package)
} catch let error as ErrorCode where error == .invalidAppleSubscriptionKeyError {
  // handle invalid apple subscription key
}

// Kotlin
if (error.code == PurchasesErrorCode.InvalidAppleSubscriptionKeyError) { /* ... */ }

On RevenueDot: RevenueDot answers POST /v1/receipts with HTTP 500 and code 7234 when a StoreKit 1 receipt arrives and the app has no In-App Purchase key, when the key is incomplete or not a valid .p8, and when Apple rejects it. It uses 500 on purpose, so the SDK keeps the purchase and retries once you add the key. POST /v1/offers answers 400 with 7234 when the key is missing, which fails only that offer. See 4xx or 5xx on a receipt.