html - PHP Mailer Office 365 -

i getting started in web development , tasked creating web-mail php form. able pull resource online , works flawlessly gmail, outlook.com , every other email service throw @ it, when add office 365 account never receive message. email godaddy @a2plcpnl0560.prod.iad2.secureserver.net domain, not on office 365 email. have been through forums , don't have enough knowledge @ moment know begin tackle problem. have seen examples of phpmailer being used , attempted make code work on domain never got confirmation message form itself. not sure if there need configure in admin center of office 365 work or not. information appreciated.

<?php  if(isset($_post['email'])) {     // edit 2 lines below required     $email_to = "info@office365.com";     $email_subject = "inquiry";      function died($error) {         // error code can go here         echo "we sorry, there error(s) found form submitted. ";         echo "these errors appear below.<br /><br />";         echo $error."<br /><br />";         echo "please go , fix these errors.<br /><br />";         die();     }      // validation expected data exists      if(!isset($_post['first_name']) ||        !isset($_post['last_name']) ||        !isset($_post['email']) ||        !isset($_post['telephone']) ||        !isset($_post['comments'])) {         died('we sorry, there appears problem form submitted.');     }      $first_name = $_post['first_name'];     // required     $last_name = $_post['last_name'];     // required     $email_from = $_post['email'];     // required     $telephone = $_post['telephone'];     // not required     $comments = $_post['comments'];     // required     $error_message = "";     $email_exp = '/^[a-za-z0-9._%-]+@[a-za-z0-9.-]+\.[a-za-z]{2,4}$/';      if(!preg_match($email_exp,$email_from)) {         $error_message .= 'the email address entered not appear valid.<br />';     }      $string_exp = "/^[a-za-z .'-]+$/";      if(!preg_match($string_exp,$first_name)) {         $error_message .= 'the first name entered not appear valid.<br />';     }       if(!preg_match($string_exp,$last_name)) {         $error_message .= 'the last name entered not appear valid.<br />';     }       if(strlen($comments) < 2) {         $error_message .= 'the comments entered not appear valid.<br />';     }       if(strlen($error_message) > 0) {         died($error_message);     }      $email_message = "form details below.\n\n";      function clean_string($string) {         $bad = array("content-type","bcc:","to:","cc:","href");         return str_replace($bad,"",$string);     }      $email_message .= "first name: ".clean_string($first_name)."\n";     $email_message .= "last name: ".clean_string($last_name)."\n";     $email_message .= "email: ".clean_string($email_from)."\n";     $email_message .= "telephone: ".clean_string($telephone)."\n";     $email_message .= "comments: ".clean_string($comments)."\n";     // create email headers     $headers = 'from: '.$email_from."\r\n".'reply-to: '.$email_from."\r\n" .'x-mailer: php/' . phpversion();     @mail($email_to, $email_subject, $email_message, $headers);     ?> 

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