Facebook undefined index email

A classic PHP error!

The error "Facebook undefined index email" typically occurs when you're trying to access the email property of a Facebook user object, but it's not set or is not available.

Here are a few possible reasons for this error:

1. User doesn't have an email address: If the user doesn't have an email address associated with their Facebook account, the email property will not be set.
2. Email address is not publicly visible: If the user has set their email address to be private, Facebook won't return it in the user object.
3. Facebook API error: There might be an issue with your Facebook API request, such as an invalid access token or a rate limit exceeded error.

To fix this error, you can try the following:

1. Check the user's email address: Before trying to access the email property, check if it's set using isset() or array_key_exists(). For example:

   if (isset($user['email'])) {
    // Email is set, you can use it now
   } else {
    // Email is not set, handle the error
   }

2. Use a fallback value: If the email property is not set, you can use a fallback value, such as an empty string or a default email address.

   $email = isset($user['email'])? $user['email'] : '';

3. Check your Facebook API request: Verify that your Facebook API request is correct and that you're using a valid access token. You can use the Facebook Debugger tool to test your API requests and identify any issues.

Remember to always handle errors and edge cases when working with user data, especially when it comes to sensitive information like email addresses.