TYPOP3 powermail: why email to receivers is not send?

Question

I have a TYPO3 website v10 and using powermail forms.
The test mail in installtool is send good.
The mail to user is send good.
The mail to receivers is not send. This is very strange.

Here is my settings from localconf file:

'defaultMailFromAddress' => '[email protected]',
'defaultMailFromName' => '[email protected]',
'defaultMailReplyToAddress' => '[email protected]',
'defaultMailReplyToName' => '[email protected]',
'transport' => 'smtp',
'transport_sendmail_command' => '/usr/sbin/sendmail -t -i',
'transport_smtp_encrypt' => false,
'transport_smtp_password' => '123456789123456',
'transport_smtp_server' => 'smtp.office365.com',
'transport_smtp_username' => '[email protected]',

Can you please give me some idea why is the email to receivers never works?

Answer 1

Things you should check:

• what is the sender address of the mail which is sent to the receiver? You should avoid to use the email address from the form data as sender address because most mail servers check SPF records nowadays. Better use TypoScript to set a static sender address like [email protected] or [email protected]. To increase comfort for the receiver you could set a reply-to address. See here for details how to do that.
• is the subject really set? If it's empty no mail is sent.

To track problems further I suggest to use a local development environment like DDEV which provides Mailhog out of the box to intercept all mails which are sent from the webserver. This helps a lot to test mails.

Answer 2

If your receiver mail is sent as Bcc: you might have hit an incompatibility of symfony/mailer (which TYPO3 uses from v10+) used with sendmail -i -t (symfony/mailer issue).

You can work around it by using transport_sendmail_command = /usr/sbin/sendmail -bs.

This TYPO3 issue explains it, too.