Strange "reply-to" email address being generated by Marketo emails

Level 4

Strange "reply-to" email address being generated by Marketo emails

Hoping someone here can shed some light on this strange issue we are facing. 


Our reply-to email address is something generic like "". However, one of our internal team members noticed the other day that when you click "reply" in outlook, the email address that populates is something completely different. In fact, it's an email address for a company we don't even recognize. 


I looked at the emails that we are sending and we make no mention of this odd reply-to address. I tested it further by sending myself emails to a GMAIL and APPLE account, and the correct reply-to address populated. This seems to be only effecting internal users in our company.


Any idea how or why this is happening? I contacted Marketo Support but they suggested speaking to our internal IT department.



Wondering if anyone else as encountered this issue before.



Level 10 - Community Moderator

Re: Strange "reply-to" email address being generated by Marketo emails

Positively something happening inside your organization.


Most likely there's an old global address book entry that corresponds to the address.


Or some bizarre rewriting rule occurring on your server.


But when Marketo sends an email, the From: and Reply-To: are exactly as they seem, and the mail client (i.e. within your org) has only those and its own strange rules to choose from.