> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/thebergamo/react-native-fbsdk-next/llms.txt
> Use this file to discover all available pages before exploring further.

# Troubleshooting

> Common issues and solutions for React Native FBSDK Next

This guide covers common issues you might encounter when integrating the Facebook SDK into your React Native app and how to resolve them.

## Common Issues

<Accordion title="1. Android project fails to run">
  **Problem:** Your Android app crashes or fails to build after installing the SDK.

  **Solution:**

  * Make sure you've added the required code in your `AndroidManifest.xml` and `res/values/strings.xml` with your Facebook app settings
  * Verify you've followed all steps in the [Android configuration guide](https://developers.facebook.com/docs/android/getting-started/)
  * Check that your Facebook App ID and Client Token are correctly configured
  * Ensure your `strings.xml` includes:
    ```xml theme={null}
    <string name="facebook_app_id">YOUR_APP_ID</string>
    <string name="facebook_client_token">YOUR_CLIENT_TOKEN</string>
    ```
</Accordion>

<Accordion title="2. Duplicate symbol errors (iOS)">
  **Problem:** You get duplicate symbol errors when building for iOS.

  **Solution:**

  Make sure that `FBSDKCoreKit.framework`, `FBSDKLoginKit.framework`, and `FBSDKShareKit.framework` are **not** in **Link Binary with Libraries** for your root project when using CocoaPods.

  These frameworks should only be linked through CocoaPods, not manually added to your project.
</Accordion>

<Accordion title="3. Build error: 'no type or protocol named UIApplicationOpenURLOptionsKey' (iOS)">
  **Problem:** Xcode shows a compilation error about `UIApplicationOpenURLOptionsKey`.

  **Solution:**

  Your Xcode version is too old. **Upgrade to Xcode 10.0 or later**.

  This type is only available in recent versions of iOS SDK that ship with Xcode 10+.
</Accordion>

<Accordion title="4. Undefined symbols for architecture x86_64 (iOS)">
  **Problem:** You get a compilation error with undefined Swift symbols:

  ```
  Undefined symbols for architecture x86_64:
    "_swift_FORCE_LOAD$_swiftUniformTypeIdentifiers"
    "_swift_FORCE_LOAD$_swiftCoreMIDI"
    "_swift_FORCE_LOAD$_swiftWebKit"
  ```

  **Solution:**

  After [facebook-ios-sdk v7](https://github.com/facebook/facebook-ios-sdk), parts of the SDK are written in Swift. You need to coordinate Swift language usage with Objective-C.

  **Option 1: Add an empty Swift file (Recommended)**

  1. In Xcode, add a new file named `File.swift` to your main project folder
  2. When Xcode asks if you want to "Create Bridging Header", click **Yes**

  This automatically adds the required Swift library search paths to your build settings:

  ```
  $(TOOLCHAIN_DIR)/usr/lib/swift/$(PLATFORM_NAME)
  $(TOOLCHAIN_DIR)/usr/lib/swift-5.0/$(PLATFORM_NAME)
  ```

  **Option 2: Update Podfile**

  Add this to the `post_install` section of your Podfile, then run `pod deintegrate && pod install`:

  ```ruby theme={null}
  # Mixing Swift and Objective-C in a react-native project may be problematic.
  # Workaround: https://github.com/facebookarchive/react-native-fbsdk/issues/755#issuecomment-787488994
  installer.aggregate_targets.first.user_project.native_targets.each do |target|
    target.build_configurations.each do |config|
      config.build_settings['LIBRARY_SEARCH_PATHS'] = ['$(inherited)', '$(SDKROOT)/usr/lib/swift']
    end
  end
  ```

  See [this issue](https://github.com/thebergamo/react-native-fbsdk-next/issues/30) for more details.
</Accordion>

<Accordion title="5. AppLink.fetchDeferredAppLink does not work (iOS)">
  **Problem:** Deferred app links are not working on iOS.

  **Solution:**

  Both the **Facebook App** and **your app** must have **App Tracking Transparency (ATT)** permission granted for Facebook deferred app links to work.

  Make sure:

  1. Your app requests ATT permission using `requestTrackingPermissionsAsync` or similar
  2. The user has granted tracking permission to both your app and the Facebook app
  3. You've added `NSUserTrackingUsageDescription` to your `Info.plist`

  See [this related issue](https://github.com/thebergamo/react-native-fbsdk-next/issues/104#issuecomment-931488609) for more information.
</Accordion>

<Accordion title="6. Exception: 'App ID not found' (iOS)">
  **Problem:** You get an exception:

  ```
  App ID not found. Add a string value with your app ID for the key 
  FacebookAppID to the Info.plist or call [FBSDKSettings setAppID:].
  ```

  **Solution:**

  If you're certain that you have the `FacebookAppID` in your `Info.plist` or that you've called `Settings.setAppID()`, you may be able to fix it by adding the following to your `AppDelegate.m` inside the `application:didFinishLaunchingWithOptions:` method, just before the `return YES` statement:

  ```objective-c theme={null}
  [[FBSDKApplicationDelegate sharedInstance] application:application
                        didFinishLaunchingWithOptions:launchOptions];
  ```

  Make sure this initialization happens early in your app's launch cycle.
</Accordion>

<Accordion title="7. Events not showing in Facebook Events Manager">
  **Problem:** You're logging events but they don't appear in the Facebook Events Manager dashboard.

  **Solution:**

  For events to show up in the Events Manager, you need:

  1. **Run the app on a real device** (not simulator)
  2. **Have the Facebook app running in the background** and logged in to an account
  3. **Add that Facebook account as an "Advertising Account"** for your app in Facebook's dashboard
  4. **Most important:** Have **ATT (App Tracking Transparency) enabled** on both:
     * The **Facebook app**
     * **Your app**

  Facebook determines which events to show based on who is logged in on the Facebook App. Only events from accounts added as "Advertising Accounts" will be visible.

  ### How to add an Advertising Account:

  1. Go to [Facebook App Dashboard](https://developers.facebook.com/apps)
  2. Select your app
  3. Go to **Settings** > **Advanced**
  4. Under **Advertising Accounts**, add the relevant accounts
</Accordion>

<Accordion title="8. Login error on Android: 'Error logging you into this application'">
  **Problem:** When attempting to log in via the native Facebook app on Android, you get an error: "There is an error in logging you into this application."

  **Solution:**

  This typically means the appropriate **signing certificate hash** hasn't been saved to your Facebook app.

  ### For Development:

  1. Generate your development key hash:
     ```bash theme={null}
     keytool -exportcert -alias androiddebugkey -keystore ~/.android/debug.keystore | openssl sha1 -binary | openssl base64
     ```
     (Default password is usually `android`)

  2. Add it to your Facebook app dashboard under **Settings** > **Basic** > **Key Hashes**

  ### For Release (Google Play signing):

  If Google is signing your releases, you'll need to get the SHA-1 from the Play Console:

  1. Go to [Play Console](https://play.google.com/console/)
  2. Navigate to **Release** > **App signing** > **App signing key certificate**
  3. Copy the SHA-1 certificate fingerprint
  4. Convert it to base64:
     ```bash theme={null}
     echo YOUR_SHA1_HERE | xxd -r -p | openssl base64
     ```
  5. Add the resulting hash to your Facebook app settings

  ### For Internal Testing:

  If you're using App Tester for internal releases:

  1. Get the SHA-1 from **Release** > **Internal app sharing** > **Internal test certificate**
  2. Run the same command to convert it
  3. Add that hash as well

  You can find detailed instructions [here](https://developers.facebook.com/docs/facebook-login/android#6--provide-the-development-and-release-key-hashes-for-your-app).
</Accordion>

<Accordion title="9. Forced to use 'limited' login on iOS">
  **Problem:** iOS forces the limited login experience even though you didn't request it.

  **Solution:**

  Although the official documentation doesn't explicitly state this, the **App Tracking Transparency (ATT)** permission is required to use the non-limited/default login on iOS devices.

  **Note:** This works fine on Android without the permission.

  ### How to fix:

  1. Request ATT permission before attempting login:
     ```js theme={null}
     import { requestTrackingPermissionsAsync } from 'expo-tracking-transparency';
     // or use react-native-tracking-transparency

     const { status } = await requestTrackingPermissionsAsync();
     if (status === 'granted') {
       // User granted permission - default login will work
     } else {
       // User denied - limited login will be used
     }
     ```

  2. Make sure `NSUserTrackingUsageDescription` is in your `Info.plist`:
     ```xml theme={null}
     <key>NSUserTrackingUsageDescription</key>
     <string>This identifier will be used to deliver personalized ads to you.</string>
     ```

  If the user allows ATT, the default Facebook login page will open. If disabled, the limited version of login will be used, which makes some Graph API endpoints unusable.

  For more information, see [Limited Login documentation](https://developers.facebook.com/docs/facebook-login/limited-login/).
</Accordion>

## Login Doesn't Work When Facebook App is Installed

**Problem:** Login works in the browser but fails when the Facebook app is installed on the device.

**Solution:**

Make sure you've implemented the `openURL` method correctly in your `AppDelegate`. Without it, the Facebook app cannot redirect back to your app after authentication.

### For Objective-C (React Native 0.76 and below):

```objc theme={null}
- (BOOL)application:(UIApplication *)app
            openURL:(NSURL *)url
            options:(NSDictionary<UIApplicationOpenURLOptionsKey,id> *)options
{
  return [[FBSDKApplicationDelegate sharedInstance]application:app
                                                      openURL:url
                                                      options:options];
}
```

### For Swift (React Native 0.77 and above):

```swift theme={null}
public override func application(
  _ app: UIApplication,
  open url: URL,
  options: [UIApplication.OpenURLOptionsKey: Any] = [:]
) -> Bool {
  let handledByFB = ApplicationDelegate.shared.application(
    app, open: url, options: options)
  let handledBySuper = super.application(
    app, open: url, options: options)
  return handledByFB || handledBySuper
}
```

See [this issue](https://github.com/thebergamo/react-native-fbsdk-next/issues/59#issuecomment-1038149447) for more details.

## Deep Linking Conflicts with Facebook SSO

**Problem:** Using `RCTLinkingManager` causes Facebook login to fail.

**Solution:**

Always check Facebook SDK **before** `RCTLinkingManager` in the `openURL` method. If `RCTLinkingManager` is placed first, it will intercept the Facebook SSO callback URL.

### Objective-C:

```objc theme={null}
- (BOOL)application:(UIApplication *)app
            openURL:(NSURL *)url
            options:(NSDictionary<UIApplicationOpenURLOptionsKey,id> *)options
{
  // Check Facebook FIRST
  if ([[FBSDKApplicationDelegate sharedInstance] application:app openURL:url options:options]) {
    return YES;
  }
  
  // Then check RCTLinkingManager
  if ([RCTLinkingManager application:app openURL:url options:options]) {
    return YES;
  }
  
  return NO;
}
```

### Swift:

```swift theme={null}
public override func application(
  _ app: UIApplication,
  open url: URL,
  options: [UIApplication.OpenURLOptionsKey: Any] = [:]
) -> Bool {
  // IMPORTANT: Facebook SDK must be checked FIRST
  let handledByFB = ApplicationDelegate.shared.application(
    app, open: url, options: options)
  
  // Then React Native Linking
  let handledByRN = RCTLinkingManager.application(
    app, open: url, options: options)
  
  // Finally super
  let handledBySuper = super.application(
    app, open: url, options: options)
  
  return handledByFB || handledByRN || handledBySuper
}
```

## Getting Help

If you're still experiencing issues:

1. Check the [GitHub Issues](https://github.com/thebergamo/react-native-fbsdk-next/issues) for similar problems
2. Review the [Facebook SDK documentation](https://developers.facebook.com/docs/facebook-login)
3. Create a new issue with:
   * React Native version
   * react-native-fbsdk-next version
   * Platform (iOS/Android)
   * Complete error messages
   * Relevant code snippets

## See Also

* [Installation Guide](/installation)
* [Testing Guide](/guides/testing)
* [Migration Guide](/guides/migration)