Address in mailbox given [] does not comply with RFC 2822, 3.6.2. when email is in a variable

I have a correct email address. I have echoed it, but when I send it, I get the following error:

 Address in mailbox given [] does not comply with RFC 2822, 3.6.2. 

Why? I use laravel (swift mailer) to send email:

$email = [email protected]

and then when I send it, the error is thrown.

But if I directly use the string, it sends it.

Here is the block:

 Mail::send('emails.activation', $data, function($message){
            $message->to($email)->subject($subject);
        });
                ->with('title', "Registered Successfully.");

Your email variable is empty because of the scope, you should set a use clause such as:

Mail::send('emails.activation', $data, function($message) use ($email, $subject) {
    $message->to($email)->subject($subject);
});

(I'm using SwiftMailer in PHP)

I was getting an error like that when I was accidentally sending a string for $email

$email = "[email protected] <Some One>";

When what I meant to be sending was

$email = Array("[email protected]"=>"Some One");

I was accidentally running it through a stringify function that I was using for logging, so once I started sending the array again, the error went away.

Make sure your email address variable is not blank. Check using

print_r($variable_passed);