title: Can't login (PHP & MySQL)
body: <p>I'm making a complete login system. The register part works just fine but if I try to login, I just get a white screen. No errors, no redirects,... The php code does execute since my url  changes to 'login.php'. I tried multiple ways to make a login, but that dind't work either. </p>
  
  <p>Thanks in advance!</p>
  
  <pre><code>  &lt;?php
  
  session_start();
  
  if(isset($_SESSION["loggedin"]) &amp;&amp; $_SESSION["loggedin"] === true){
      header("location: index_afterlogin.html");
      exit;
  }
  
  require_once "config.php";
  
  $email = $password = "";
  $email_err = $password_err = "";
  
  if($_SERVER["REQUEST_METHOD"] == "POST"){
       if(empty(trim($_POST["email"]))){
          $email_err = "Please enter e-mail.";
      } else{
          $email = trim($_POST["email"]);
      }
  
      if(empty(trim($_POST["password"]))){
          $password_err = "Please enter your password.";
      } else{
          $password = trim($_POST["password"]);
      }
  
      if(empty($email_err) &amp;&amp; empty($password_err)){
          $sql = "SELECT userID, email, password FROM users WHERE email = ?";
  
          if($stmt = mysqli_prepare($db, $sql)){
              mysqli_stmt_bind_param($stmt, "s", $param_email);
  
              $param_email = $email;
  
              if(mysqli_stmt_execute($stmt)){
                  mysqli_stmt_store_result($stmt);
  
                  if(mysqli_stmt_num_rows($stmt) == 1){                    
                      mysqli_stmt_bind_result($stmt, $id, $email, $hashed_password);
                      if(mysqli_stmt_fetch($stmt)){
                          if(password_verify($password, $hashed_password)){
                              session_start();
  
                              // Store data in session variables
                              $_SESSION["loggedin"] = true;
                              $_SESSION["userID"] = $id;
                              $_SESSION["email"] = $email;                            
  
                              header("location: index_afterlogin.html");
                          } else{
                              $password_err = "The password you entered was not valid.";
                          }
                      }
                  } else{
                      $email_err = "No account found with that username.";
                  }
              } else{
                  echo "Oops! Something went wrong. Please try again later.";
              }
          }
  
          mysqli_stmt_close($stmt);
      }
  
      mysqli_close($db);
  }
  ?&gt;
  </code></pre>