Why can some emails display as “on behalf of” or “via”?
Regardless of your ‘From’ address settings which you choose for each message, it may happen that some of your subscribers see:
[firstname.lastname@example.org] on behalf of
From: John Smith
[your_from_email] via getresponse.com
The situation described above may occur for only some of your subscribers using certain email clients and email applications like Gmail and Outlook. To avoid this, you would need to set up a DKIM signature for your sending domain. This manual will provide instructions on how to set that up.