"Note: When sending mail, the mail must contain a From header. This can be set with the additional_headers parameter, or a default can be set in php.ini. Failing to do this will result in an error message similar to Warning: mail(): "sendmail_from" not set in php.ini or custom "From:" header missing. The From header sets also Return-Path under Windows."

The content type header should be honored if the mail server supports it.

        if (extension_loaded('imap')) {
            $this->header = "From: =?UTF-8?Q?" .imap_8bit($name) ."?=". "<$mail>\n";
        }
        else
            $this->header = "From: =?UTF-8?B?" .base64_encode($name) ."?=". "<$mail>\n";

        $bcc = get_company_pref('bcc_email');
        if ($bcc)
            $this->bcc[] = $bcc;
    }

and

function subject($subject)
    {
        if (extension_loaded('imap')) {
            $this->subject = "=?UTF-8?Q?" .imap_8bit($subject) ."?=";
        }
        else
            $this->subject = "=?UTF-8?B?" . base64_encode($subject) ."?=";

    }

Functions and tested

@campbell, Hi, the problem is not with the body, its with the header and the subject.

It seems from this post that support for unicode email addresses in the local part is relatively new. e.g. Postfix supported it in 2014.  It very much depends on what email software your server (or ISP) has installed to support the sending of email.  I suspect that if you use gmail, or google apps for business then you wouldn't have any problems (assuming the content header is set correctly).  Using Postfix for example you would need to ensure that version 3.0 or greater is installed.  In the debian world this would be Debian Stretch.  Wheezy and Jessie are both on Postfix 2.x.  You can find further information on SMTPUTF8 support and links to relevant RFC on the Postfix SMTPUFT8 page.

To be safe, I would suggest that all email addresses in *your* organization use the 128 lowercase ascii characters as required under the old standard.

I will try to do an if / else tomorrow. Trying to think how I will test it... any ideas?

IMAP
====

if (extension_loaded('imap')) {

....
....

}

function subject($subject)
    {
        $this->subject = $subject;
    }

to:-

function subject($subject)
    {
        $this->subject = "=?UTF-8?B?" . base64_encode($subject) ."?=";
    }

or

function subject($subject)
    {
        $this->subject = "=?UTF-8?Q?" .imap_8bit($subject) ."?=";//you will need the imap module enabled
    }

I believe this only leaves the email addresses, which 'generally' are not allowed to include diacriticals. (though there is some debate about this - Google 'Are accents allowed in email addresses' - for starters)

Very interested in your comments.

What is the history / background? ie Did company name and email subject function with accents before the change to utf-8?

/Joe

Replace class.mail.inc line 49 from:-

$this->header = "From: $name <$mail>\n";

with either:-

$this->header = "From: =?UTF-8?B?" .base64_encode($name) ."?=". "<$mail>\n";

OR

$this->header = "From: =?UTF-8?Q?" .imap_8bit($name) ."?=". "<$mail>\n"; //you will need the imap module enabled

depending if you want base64 or imap

You should now be able to use any diacritical in your company name.

@apmuthu I'm struggling with the  mb_send_mail() & mb_encode_mimeheader(), from my understanding this encodes the whole header: When I got it to work it actually used my servers email address as the from, whereas in the above solution the actual servers email address is hidden and the company email address is shown as per FA functionality.  Can you help?

The mb_encode_mimeheader() method is also listed.

From my understanding $name is not encoded so accented char will never work, this post at stackexchange pointed me in the right direction, so changing class.mail.inc line 49 from:-

$this->header = "From: $name <$mail>\n";

to

$this->header = "From: =?UTF-8?B?" .base64_encode($name)."?=";

does work, BUT:-

does NOT include the newline \n so the from $name is followed by the Bcc: bccemailaddress@example.com

So I tried to introduce a new line with the following code:-

$this->header = "From: =?UTF-8?B?" .base64_encode($name)."?=", "\n";
and
$this->header = "From: =?UTF-8?B?" .base64_encode($name)."?=". "\n";

but neither of these work as the from is now the base64 code

If anyone knows a little more php than me can help add a new line please do, will sleep on it.

$this->header = "From: $name <$mail>\n";

to

$this->header = "From: 'Psicopedagógico' <$mail>\n";

I first tried with a normal 'o' and all emails were sent perfectly.

When I replaced the normal 'o' with an accented 'ó', emails failed to send with the same fault code:-
    SMTP error from remote mail server after end of data:
    550 From contains invalid characters.

For me this says that the problem is in the encoding of the email header not with the database.

I re-tried:-

var $charset = 'iso-8859-1';
to
var $charset = 'utf-8'; //also tried utf8
and
var $charset = 'utf8_unicode_ci';
and
var $charset = 'utf8mb4_unicode_ci';

All failed. I've since read that all SMPT headers should be ASCII encoded. (I did try ASCII & even 8BITMIME but maybe unsurprisingly they failed too as believe they don't include an accent 'ó')

I'm now looking for where the encoding from charset happens, And I'can't seem to find it?

Not sure what you mean about url encoding?

The problem is in company name in company configuration, not in the email address: I have tried quoted format, this returns '&quot' in the email company name, I've also tried psicopedag&oacute;gico

I assume:-
HTML Entity (decimal)     &#243;
HTML Entity (hex)     &#xf3;
will have the same result as &oacute; unless you can tell me otherwise?