Email is configured correctly, but refused by recepient

Hey there!

So I'm having an issue with emails being recived by the customer. Emails generated by LiteCart are sent correctly but rejected by the recepient mail service. DMARC is on point, all other safety requirements are there as well.
Ideas where to look to fix it?

GMX says that LiteCart generated emails are missing sender information basically.

You need to change your password as you posted it here in the forum.

Looking at your sender name, could you try a regular name without specials & : ?

[quote]Looking at your sender name, could you try a regular name without specials & : ?[/quote]
Tried that. Same results.

What was the name you tried?

[quote]What was the name you tried?[/quote]
 SPQR and CO

What happens if you edit includes/entities/ent_email.inc.php and substitute the format_contact() function with this:

        return '"'. addcslashes($contact['name'], '"') .'" <'. $contact['email'] .'>';
    }```

I get error code after placing order:

Fatal error: syntax error, unexpected token "if", expecting "function" or "const" in ~/includes/entities/ent_email.inc.php (Line 235)

After replacing:

public function format_contact($contact) {

      if (empty($contact['name']) || $contact['name'] == $contact['email']) {
        return $contact['email'];
      }

with

public function format_contact($contact) {
        return '"'. addcslashes($contact['name'], '"') .'" <'. $contact['email'] .'>';
    }

You did not replace the entire function, just a few lines.
https://github.com/litecart/litecart/blob/2.5.5/public_html/includes/entities/ent_email.inc.php#L231-L246

[quote]You did not replace the entire function, just a few lines.
https://github.com/litecart/litecart/blob/2.5.5/public_html/includes/entities/ent_email.inc.php#L231-L246[/quote]

Holy sh*t, it worked!
Thanks a lot, Tim!
I'll remove sensitive stuff from original post now.

This might mean the receiving web server is always expecting to wrap the name in double quotes. I thought the standard was to use quotations if the name contained a comma or special charcters.