PHP mail function doesn't complete sending of e-mail

    $name = $_POST['name'];
    $email = $_POST['email'];
    $message = $_POST['message'];
    $from = 'From:'; 
    $to = '[email protected]'; 
    $subject = 'Customer Inquiry';
    $body = "From: $name/n E-Mail: $email/n Message:/n $message";

    if ($_POST['submit']) {
        if (mail ($to, $subject, $body, $from)) { 
            echo '<p>Your message has been sent!</p>';
        } else { 
            echo '<p>Something went wrong, go back and try again!</p>'; 

I’ve tried creating a simple mail form. The form itself is on my index.html page, but submits to a separate “thank you for your submission” page, thankyou.php, where the above php code is embedded.
The code submits perfectly, but never sends an email. please help.

There are a variety of reasons your script appears to not be sending emails. It’s difficult to diagnose these things unless there is an obvious syntax error. Without one you need to run through the checklist below to find any potential pitfalls you may be encountering.

Make sure error reporting is enabled and set to report all errors

Error reporting is essential to rooting out bugs in your code and general errors that PHP encounters. Error reporting needs to be enabled to receive these errors. Placing the following code at the top of your PHP files (or in a master configuration file) will enable error reporting.

ini_set('display_errors', 'On');

See this Stack Overflow answer for more details on this.

Make sure the mail() function is called

It may seem silly but a common error is to forget to actually place the mail() function in your code. Make sure it is there and not commented out.

Check the server’s mail logs

Your web server should be logging all attempts to send emails through it. The location of these logs will vary (you may need to ask your server administrator where they are located) but they can commonly be found in a user’s root directory under logs. Inside will be error messages the server reported, if any, related to your attempts to send emails.

Check for Port connection failure

Port block is a very common problem which most developers face while integrating their code to deliver emails using SMTP. And, this can be easily traced at the server maillogs (the location of server of mail log can vary from server to server, as explained above). In case you are on a shared hosting server, the ports 25 and 587 remain blocked by default. This block is been purposely done by your hosting provider. This is true even for some of the dedicated servers. When these ports are blocked, try to connect using port 2525. If you find that port is also blocked, then the only solution is to contact your hosting provider to unblock these ports.

Most of the hosting providers block these email ports to protect their network from sending any spam emails.

Use ports 25 or 587 for plain/TLS connections and port 465 for SSL connections. For most users, it is suggested to use port 587 to avoid rate limits set by some hosting providers.

Don’t use the error suppression operator

When the error suppression operator @ is prepended to an expression in PHP, any error messages that might be generated by that expression will be ignored. There are circumstances where using this operator is necessary but sending mail is not one of them.

If your code contains @mail(…) then you may be hiding important error messages that will help you debug this. Remove the @ and see if any errors are reported.

It’s only advisable when you check with error_get_last() right afterwards for concrete failures.

Check the mail() return value

The mail() function:

Returns TRUE if the mail was successfully accepted for delivery, FALSE otherwise. It is important to note that just because the mail was accepted for delivery, it does NOT mean the mail will actually reach the intended destination.

This is important to note because:

  • If you receive a FALSE return value you know the error lies with your server accepting your mail. This probably isn’t a coding issue but a server configuration issue. You need to speak to your system administrator to find out why this is happening.
  • If your receive a TRUE return value it does not mean your email will definitely be sent. It just means the email was sent to its respective handler on the server successfully by PHP. There are still more points of failure outside of PHP’s control that can cause the email to not be sent.

So FALSE will help point you in the right direction whereas TRUE does not necessarily mean your email was sent successfully. This is important to note!

Make sure your allows you to send emails and does not limit mail sending

Many shared webhosts, especially free webhosting providers, either do not allow emails to be sent from their servers or limit the amount that can be sent during any given time period. This is due to their efforts to limit spammers from taking advantage of their cheaper services.

If you think your host has emailing limits or blocks the sending of emails, check their FAQs to see if they list any such limitations. Otherwise, you may need to reach out to their support to verify if there are any restrictions in place around the sending of emails.

Check spam folders; prevent emails from being flagged as spam

Oftentimes, for various reasons, emails sent through PHP (and other server-side programming languages) end up in a recipient’s spam folder. Always check there before troubleshooting your code.

To avoid mail sent through PHP from being sent to a recipient’s spam folder, there are various things you can do, both in your PHP code and otherwise, to minimize the chances your emails are marked as spam. Good tips from Michiel de Mare include:

  • Use email authentication methods, such as SPF, and DKIM to prove that your emails and your domain name belong together, and to prevent spoofing of your domain name. The SPF website includes a wizard to generate the DNS information for your site.
  • Check your reverse DNS to make sure the IP address of your mail server points to the domain name that you use for sending mail.
  • Make sure that the IP-address that you’re using is not on a blacklist
  • Make sure that the reply-to address is a valid, existing address.
  • Use the full, real name of the addressee in the To field, not just the email-address (e.g. “John Smith” <[email protected]> ).
  • Monitor your abuse accounts, such as [email protected] and [email protected] That means – make sure that these accounts exist, read what’s sent to them, and act on complaints.
  • Finally, make it really easy to unsubscribe. Otherwise, your users will unsubscribe by pressing the spam button, and that will affect your reputation.

See How do you make sure email you send programmatically is not automatically marked as spam? for more on this topic.

Make sure all mail headers are supplied

Some spam software will reject mail if it is missing common headers such as “From” and “Reply-to”:

$headers = array("From: [email protected]",
    "Reply-To: [email protected]",
    "X-Mailer: PHP/" . PHP_VERSION
$headers = implode("/r/n", $headers);
mail($to, $subject, $message, $headers);

Make sure mail headers have no syntax errors

Invalid headers are just as bad as having no headers. One incorrect character could be all it takes to derail your email. Double-check to make sure your syntax is correct as PHP will not catch these errors for you.

$headers = array("From [email protected]", // missing colon
    "Reply To: [email protected]",      // missing hyphen
    "X-Mailer: "PHP"/" . PHP_VERSION      // bad quotes

Make sure the recipient value is correct

Sometimes the problem is as simple as having an incorrect value for the recipient of the email. This can be due to using an incorrect variable.

$to = '[email protected]';
// other variables ....
mail($recipient, $subject, $message, $headers); // $recipient should be $to

Another way to test this is to hard code the recipient value into the mail() function call:

mail('[email protected]', $subject, $message, $headers); 

This can apply to all of the mail() parameters.

Send to multiple accounts

To help rule out email account issues, send your email to multiple email accounts at different email providers. If your emails are not arriving at a user’s Gmail account, send the same emails to a Yahoo account, a Hotmail account, and a regular POP3 account (like your ISP-provided email account).

If the emails arrive at all or some of the other email accounts, you know your code is sending emails but it is likely that the email account provider is blocking them for some reason. If the email does not arrive at any email account, the problem is more likely to be related to your code.

Make sure the code matches the form method

If you have set your form method to POST, make sure you are using $_POST to look for your form values. If you have set it to GET or didn’t set it at all, make sure you using $_GET to look for your form values.

Make sure the Web host supports sending email

Some Web hosting providers do not allow or enable the sending of emails through their servers. The reasons for this may vary but if they have disabled the sending of mail you will need to use an alternative method that uses a third party to send those emails for you.

An email to their technical support (after a trip to their online support or FAQ) should clarify if email capabilities are available on your server.

Make sure the localhost mail server is configured

If you are developing on your local workstation using WAMP, MAMP, or XAMPP, an email server is probably not installed on your workstation. Without one, PHP cannot send mail by default.

You can overcome this by installing a basic mail server. For Windows you can use the free Mercury Mail.

You can also use SMTP to send your emails. See this great answer from Vikas Dwivedi to learn how to do this.

Enable PHP’s custom mail.log

In addition to your MTA’s and PHP’s log file, you can enable logging for the mail() function specifically. It doesn’t record the complete SMTP interaction, but at least function call parameters and invocation script.

ini_set("mail.log", "/tmp/mail.log");
ini_set("mail.add_x_header", TRUE);

See for details. (It’s best to enable these options in the php.ini or .user.ini or .htaccess perhaps.)

Use a different mailer

PHP’s built in mail() function is handy and often gets the job done but it has its shortcomings. Fortunately there are alternatives that offer more power and flexibility including handling a lot of the issues outlined above. One that would might consider using is the popular PHPMailer or SwiftMailer, or even the older PEAR::Mail.

Add mail header in mail function

$header = "From: [email protected]/r/n"; 
$header.= "MIME-Version: 1.0/r/n"; 
$header.= "Content-Type: text/html; charset=ISO-8859-1/r/n"; 
$header.= "X-Priority: 1/r/n"; 

$status = mail($to, $subject, $message, $header);

    echo '<p>Your mail has been sent!</p>';
} else { 
    echo '<p>Something went wrong, Please try again!</p>'; 
  1. Always try sending headers in mail function.
  2. If you are sending mail through localhost then do the smtp settings for sending mail.
  3. If you are sending mail through server then check the email sending feature is enabled on your server.

are you using SMTP configuration for sending your email?
try using phpmailer instead. you can download the library from i created my email sending this way:

function send_mail($email, $recipient_name, $message='')

    $mail = new PHPMailer();

    $mail->IsSMTP();                                      // set mailer to use SMTP
    $mail->Host = "";  // specify main and backup server
    $mail->SMTPAuth = true;     // turn on SMTP authentication
    $mail->Username = "myusername";  // SMTP username
    $mail->Password = "[email protected]"; // SMTP password

    $mail->From = "[email protected]";
    $mail->FromName = "System-Ad";
    $mail->AddAddress($email, $recipient_name);

    $mail->WordWrap = 50;                                 // set word wrap to 50 characters
    $mail->IsHTML(true);                                  // set email format to HTML (true) or plain text (false)

    $mail->Subject = "This is a Sampleenter code here Email";
    $mail->Body    = $message;
    $mail->AltBody = "This is the body in plain text for non-HTML mail clients";    
    $mail->AddEmbeddedImage('images/logo.png', 'logo', 'logo.png');

       echo "Message could not be sent. <p>";
       echo "Mailer Error: " . $mail->ErrorInfo;

    echo "Message has been sent";

it worked for me on 000webhost by doing the following :

$headers  = "MIME-Version: 1.0" . "/r/n";
$headers .= "Content-type: text/html; charset=iso-8859-1" . "/r/n";
$headers .= "From: ". $from. "/r/n";
$headers .= "Reply-To: ". $from. "/r/n";
$headers .= "X-Mailer: PHP/" . phpversion();
$headers .= "X-Priority: 1" . "/r/n"; 

Enter directly the email address when sending the email

mail('[email protected]', $subject, $message, $headers)

Use ” and not “”

This code works but the email was received with half an hour lag

Just add some headers before sending mail:

$name = $_POST['name'];
$email = $_POST['email'];
$message = $_POST['message'];
$from = 'From:'; 
$to = '[email protected]'; 
$subject = 'Customer Inquiry';
$body = "From: $name/n E-Mail: $email/n Message:/n $message";

$headers .= "MIME-Version: 1.0/r/n";
$headers .= "Content-type: text/html/r/n";
$headers .= 'From: [email protected]' . "/r/n" .
'Reply-To: [email protected]' . "/r/n" .
'X-Mailer: PHP/' . phpversion();

mail($to, $subject, $message, $headers);

And one more thing. The mail() function is not working in localhost. Upload your code to a server and try.

Try these two thigs separately and together:

  1. remove the if($_POST[‘submit’]){}
  2. remove $from (just my gut)

Mostly the mail() function is disabled in shared hosting.
A better option is to use SMTP. The best option would be Gmail or SendGrid.


    $SmtpPort="2525"; //default


class SMTPClient

    function SMTPClient ($SmtpServer, $SmtpPort, $SmtpUser, $SmtpPass, $from, $to, $subject, $body)

        $this->SmtpServer = $SmtpServer;
        $this->SmtpUser = base64_encode ($SmtpUser);
        $this->SmtpPass = base64_encode ($SmtpPass);
        $this->from = $from;
        $this->to = $to;
        $this->subject = $subject;
        $this->body = $body;

        if ($SmtpPort == "") 
            $this->PortSMTP = 25;
            $this->PortSMTP = $SmtpPort;

    function SendMail ()
        $newLine = "/r/n";
        $headers = "MIME-Version: 1.0" . $newLine;  
        $headers .= "Content-type: text/html; charset=iso-8859-1" . $newLine;  

        if ($SMTPIN = fsockopen ($this->SmtpServer, $this->PortSMTP)) 
            fputs ($SMTPIN, "EHLO ".$HTTP_HOST."/r/n"); 
            $talk["hello"] = fgets ( $SMTPIN, 1024 ); 
            fputs($SMTPIN, "auth login/r/n");
            fputs($SMTPIN, $this->SmtpUser."/r/n");
            fputs($SMTPIN, $this->SmtpPass."/r/n");
            fputs ($SMTPIN, "MAIL FROM: <".$this->from.">/r/n"); 
            $talk["From"] = fgets ( $SMTPIN, 1024 ); 
            fputs ($SMTPIN, "RCPT TO: <".$this->to.">/r/n"); 
            $talk["To"] = fgets ($SMTPIN, 1024); 
            fputs($SMTPIN, "DATA/r/n");
            $talk["data"]=fgets( $SMTPIN,1024 );
            fputs($SMTPIN, "To: <".$this->to.">/r/nFrom: <".$this->from.">/r/n".$headers."/n/nSubject:".$this->subject."/r/n/r/n/r/n".$this->body."/r/n./r/n");
            //CLOSE CONNECTION AND EXIT ... 
            fputs ($SMTPIN, "QUIT/r/n"); 
        return $talk;


    $to = "";
    $from = $_POST['email'];
    $subject = "Enquiry";
    $body = $_POST['name'].'</br>'.$_POST['companyName'].'</br>'.$_POST['tel'].'</br>'.'<hr />'.$_POST['message'];
    $SMTPMail = new SMTPClient ($SmtpServer, $SmtpPort, $SmtpUser, $SmtpPass, $from, $to, $subject, $body);
    $SMTPChat = $SMTPMail->SendMail();

If you only use the mail()function, you need to complete the config file.

You need to open the mail expansion, and set the SMTP smtp_port and so on, and most important, your username and your password. Without that, mail cannot be sent. Also, you can use PHPMail class to send.

You can use config email by codeigniter, example using smtp (simple way) :

$config = Array(
        'protocol' => 'smtp',
        'smtp_host' => '', //your smtp host
        'smtp_port' => 26, //default port smtp
        'smtp_user' => '[email protected]',
        'smtp_pass' => 'password',
        'mailtype' => 'html',
        'charset' => 'iso-8859-1',
        'wordwrap' => TRUE
$message = 'Your msg';
$this->load->library('email', $config);
$this->email->from('[email protected]', 'Title');
$this->email->to('[email protected]');

   //conditional true

It’s works for me!

For anyone who finds this going forward, I would not recommend using mail. There’s some answers that touch on this, but not the why of it.

PHP’s mail function is not only opaque, it fully relies on whatever MTA you use (i.e. Sendmail) to do the work. mail will ONLY tell you if the MTA failed to accept it (i.e. Sendmail was down when you tried to send). It cannot tell you if the mail was successful because it’s handed it off. As such (as John Conde’s answer details), you now get to fiddle with the logs of the MTA and hope that it tells you enough about the failure to fix it. If you’re on a shared host or don’t have access to the MTA logs, you’re out of luck. Sadly, the default for most vanilla installs for Linux handle it this way.

A mail library (PHPMailer, Zend Framework 2+, etc), does something very different from mail. What they do is they open a socket directly to the receiving mail server and then send the SMTP mail commands directly over that socket. In other words, the class acts as its own MTA (note that you can tell the libraries to use mail to ultimately send the mail, but I would strongly recommend you not do that).

What this means for you is that you can then directly see the responses from the receiving server (in PHPMailer, for instance, you can turn on debugging output). No more guessing if a mail failed to send or why.

If you’re using SMTP (i.e. you’re calling isSMTP()), you can get a detailed transcript of the SMTP conversation using the SMTPDebug property.

Set this option by including a line like this in your script:

$mail->SMTPDebug = 2;

You also get the benefit of a better interface. With mail you have to set up all your headers, attachments, etc. With a library, you have a dedicated function to do that. It also means the function is doing all the tricky parts (like headers).

I think this should do the trick. I just added an if(isset and added concatenation to the variables in the body to separate PHP from HTML.

    $name = $_POST['name'];
    $email = $_POST['email'];
    $message = $_POST['message'];
    $from = 'From:'; 
    $to = '[email protected]'; 
    $subject = 'Customer Inquiry';
    $body = "From:" .$name."/r/n E-Mail:" .$email."/r/n Message:/r/n" .$message;

if (isset($_POST['submit'])) 
    if (mail ($to, $subject, $body, $from)) 
        echo '<p>Your message has been sent!</p>';
        echo '<p>Something went wrong, go back and try again!</p>'; 

$name = $_POST['name'];
$email = $_POST['email'];
$reciver = '/* Reciver Email address */';
if (filter_var($reciver, FILTER_VALIDATE_EMAIL)) {
    $subject = $name;
    // To send HTML mail, the Content-type header must be set.
    $headers = 'MIME-Version: 1.0' . "/r/n";
    $headers .= 'Content-type: text/html; charset=iso-8859-1' . "/r/n";
    $headers .= 'From:' . $email. "/r/n"; // Sender's Email
    //$headers .= 'Cc:' . $email. "/r/n"; // Carbon copy to Sender
    $template = '<div style="padding:50px; color:white;">Hello ,<br/>'
        . '<br/><br/>'
        . 'Name:' .$name.'<br/>'
        . 'Email:' .$email.'<br/>'
        . '<br/>'
        . '</div>';
    $sendmessage = "<div style=/"background-color:#7E7E7E; color:white;/">" . $template . "</div>";
    // Message lines should not exceed 70 characters (PHP rule), so wrap it.
    $sendmessage = wordwrap($sendmessage, 70);
    // Send mail by PHP Mail Function.
    mail($reciver, $subject, $sendmessage, $headers);
    echo "Your Query has been received, We will contact you soon.";
} else {
    echo "<span>* invalid email *</span>";

Try this

$to = "[email protected], [email protected]";
$subject = "HTML email";

$message = "
       <title>HTML email</title>
      <p>This email contains HTML Tags!</p>

// Always set content-type when sending HTML email
$headers = "MIME-Version: 1.0" . "/r/n";
$headers .= "Content-type:text/html;charset=UTF-8" . "/r/n";

// More headers
$headers .= 'From: <[email protected]>' . "/r/n";
$headers .= 'Cc: [email protected]' . "/r/n";


Try this

if ($_POST['submit']) {
    $success= mail($to, $subject, $body, $from);
        echo '
        <p>Your message has been sent!</p>
    } else { 
        echo '
        <p>Something went wrong, go back and try again!</p>

If you’re having trouble sending mails with PHP, consider an alternative like PHPMailer or SwiftMailer.

I usually use SwiftMailer whenever I need to send mails with PHP.

Basic usage :

require 'mail/swift_required.php';

$message = Swift_Message::newInstance()
    // The subject of your email
    ->setSubject('Jane Doe sends you a message')
    // The from address(es)
    ->setFrom(array('[email protected]' => 'Jane Doe'))
    // The to address(es)
    ->setTo(array('[email protected]' => 'Frank Stevens'))
    // Here, you put the content of your email
    ->setBody('<h3>New message</h3><p>Here goes the rest of my message</p>', 'text/html');

if (Swift_Mailer::newInstance(Swift_MailTransport::newInstance())->send($message)) {
    echo json_encode([
        "status" => "OK",
        "message" => 'Your message has been sent!'
} else {
    echo json_encode([
        "status" => "error",
        "message" => 'Oops! Something went wrong!'

See the official documentation for more info on how to use SwiftMailer.

You can use empty() and isset() functions. If you want to make it work with different files, just modify the action=’yourphp.php’ to the html I’m giving you, and store the PHP script to that yourphp.php file. Also you need to change your index.html into index.php to activate PHP functionality.



    $name = $_POST['name'];
    $email = $_POST['email'];
    $message = $_POST['message'];
    $from = 'From:'; 
    $to = '[email protected]'; 
    $subject = 'Customer Inquiry';
    $body = "From: $name/n E-Mail: $email/n Message:/n $message";

    if ($_POST['submit']){
                if (!(empty($_POST['name']))) {
                        if (!(empty($_POST['email']))){
                            if (!(empty($_POST['message']))){
                                mail ($to, $subject, $body, $from);
                                echo '<p>Your message has been sent!</p>';
                                echo '<p>Fill your message please.</p>';}
                        }else {
                            echo '<p>Fill your email please.</p>';}
                    echo '<p>Fill your name please.</p>';}              
            echo '<p>Fill the form.</p>';}


    <form method="post" action="?">
            <tr><td>Name</td><td><input type='text' name='name' id='name'/></td></tr>
            <tr><td>Email</td><td><input type='text' name='email' id='email'/></td></tr>
            <tr><td>Message</td><td><input type='text' name='message' id='message'/></td></tr>
            <tr><td></td><td><input type='submit' name='submit' id='submit'/></td></tr>

Best Regards!

First of all,

You might have to many parameters for the mail() function…
You are able to have 5 max. mail(to,subject,message,headers,parameters);
As far as the $from variable goes, that should automatically come from your webhost if your using linux cPanel. It automatically comes from your cPanel username and ip address.

$name = $_POST['name'];
$email = $_POST['email'];
$message = $_POST['message'];
$from = 'From:'; 
$to = '[email protected]'; 
$subject = 'Customer Inquiry';
$body = "From: $name/n E-Mail: $email/n Message:/n $message";

Also make sure you have the correct order of variables in your mail() function.
the mail($to,$subject,$message,etc.) in that order, or else there is a chance of it not working.
Let me know if this helps…

If you are running this code on a local server (i.e your computer for development purposes) it wont send the email to the recipient. What will happen is, it will create a .txt file in a folder named mailoutput.

In the case if you are using a free hosing service like 000webhost or hostinger, those service providers disable the mail() function to prevent unintended uses of email spoofing, spamming etc. I prefer you to contact them to see whether they support this feature.

If you are sure that the service provider supports the mail() function, you can check this PHP manual for further reference,
PHP mail()

To check weather your hosting service support the mail() function, try running this code, (Remember to change the recipient email address)

    $to      = '[email protected]';
    $subject = 'the subject';
    $message = 'hello';
    $headers = 'From: [email protected]' . "/r/n" .
        'Reply-To: [email protected]' . "/r/n" .
        'X-Mailer: PHP/' . phpversion();

    mail($to, $subject, $message, $headers);

Hope this helped.

This will only affect a small handful of users, but I’d like it documented for that small handful. This member of that small handful spent 6 hours troubleshooting a working PHP mail script because of this issue.

If you’re going to a university that runs XAMPP from, you should know what our professor didn’t tell us: The AceITLab firewall (not the Windows firewall) blocks MercuryMail in XAMPP. You’ll have to use an alternative mail client, pear is working for us. You’ll have to send to a Gmail account with low security settings.

Yes, I know, this is totally useless for real world email. However, from what I’ve seen, academic settings and the real world often have precious little in common.

For those who do not want to use external mailers and want to mail() on a dedicated linux server.

The way how php mails is described in php.ini in section [mail function].
Parameter sendmail-path describes how sendmail is called. Default value is sendmail -t -i, so if you get working sendmail -t -i < message.txt in linux console – you will be done. You could also add mail.log to debug and be sure mail() is really called.

Different MTA can implement sendmail. For example, in debian default is postfix. Configure your MTA to send mail and test it from console with sendmail -v -t -i < message.txt. File message.txt should contain all headers of a message and a body, destination addres for envelope will be taken from To: header. Example:

From: [email protected]
To: [email protected]
Subject: Test mail via sendmail.

Text body.

I prefere to use ssmtp as MTA because it is simple and do not require running daemon with opened ports. ssmtp fits only for local mail send, it also can send authenticated email via your account on a public mail service. Install ssmtp and edit config /etc/ssmtp/ssmtp.conf. To be able also to recive local system mail to unix accounts(from cron jobs, for example) configure /etc/ssmtp/revaliases file.

Here is my config for my account on Yandex mail:

[email protected]
[email protected]
    $name       = $_POST['name'];
    $email  = $_POST['email'];
    $message    = $_POST['message'];
    $from       = 'Sender <>'; 
    $to         = '[email protected]'; 
    $subject    = 'Customer Inquiry';
    $body       = "From: $name/n E-Mail: $email/n Message:/n $message";
    $headers.='X-Mailer: PHP/' . phpversion().'/r/n';
    $headers.= 'MIME-Version: 1.0' . "/r/n";
    $headers.= 'Content-type: text/html; charset=iso-8859-1 /r/n';

    if ($_POST['submit']) {
        if (mail ($to, $subject, $body, $headers,"-f$from")) { 
            echo '<p>Your message has been sent!</p>';
        } else { 
            echo '<p>Something went wrong, go back and try again!</p>'; 

In Linux systems, PHP mail() uses sendmail application to send mails from the system.

Check whether sendmail application is installed.

dnf install sendmail

And also check whether the sendmail service is started.

sudo service sendmail start

You should use the htmlspecialchars() function to avoid such errors. This usually happens if user puts an email or any query with an “apostrophe”.

Here’s the perfect code:

Be sure you validate all the user inputs. MOST IMPORTANTLY, check your Spam folder because 90% of simple fake mails are dumped in spam. If you are on Xammp server, check your mailoutput folder. There you’ll see all those mails in notepad files.

I hope this answer helped you without tough complications. 🙂