A constituent pointed out that she received an emailed invoice from "[4-digit-number]@[host-domain]" rather than from our normal organization email address. (We use CiviHosting's shared server.)
I haven't made any changes to the Civi settings, and upon checking, the default From Email Address is set to "office@[our-domain]" as expected and the mailer is set to "mail()".
Other emails are sent as expected:
- individual emails
- bulk email
- automatic receipts for online contributions
- automatic registration confirmations for events
I have discovered that when a back-end user triggers "Send Invoice" for a contribution, if one of that user's email addresses is chosen as From Address to use, it is ignored and the host-server address is used. If, however, one of the CiviMail-configured From Addresses is used, it is sent properly.
I just became aware of this last week, and I have a copy of an invoice sent a few weeks before that with the correct From address, so something happened within that window of time to cause a change.
civi 5.9.0, joomla 3.9.5