This app has no Android Key hashes configured. - Login with Facebook SDK

You need not generate your hash key. When you will try to access facebook from your app, you will get an error msg saying following "[Hash Key]" is not registered or configured. Just copy that key and go to developer.facebook.com where you have registered your app for facebook verification and include under key hashes.

Remember : For every device, the hash key may be different. You need to include it freshly.

By default this key should do : 2jmj7l5rSw0yVb/vlWAYkK/YBwk=

Also, before everything, you need to provide facebook with your App details, along with screenshots of where you are using facebook features and reasons for why you are using. They need to verify that.

To generate a hash of your release key, run the following command on Mac or Windows substituting your release key alias and the path to your keystore. On OS X, run:

keytool -exportcert -alias <RELEASE_KEY_ALIAS> -keystore <RELEASE_KEY_PATH> | openssl sha1 -binary | openssl base64

On Windows, use:

keytool -exportcert -alias <RELEASE_KEY_ALIAS> -keystore <RELEASE_KEY_PATH> | openssl sha1 -binary | openssl base64

Ref: https://developers.facebook.com/docs/android/getting-started/#create_hash

If you haven't published your app and just want to use the debug version hash, you can get it from your debug keystore with this command:

keytool -exportcert -alias androiddebugkey -keystore ~/.android/debug.keystore | openssl sha1 -binary | openssl base64

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