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Author Topic: Best Practices: Spoofing the Sender  (Read 38974 times)


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Best Practices: Spoofing the Sender
« on: April 15, 2010, 12:56:07 PM »

Our company sends email on behalf of our customers, so we spoof the sender to be the customer's email.  This clearly is a practice done by many of the large emailers, like SalesForce, VerticalResponse, etc.

However, what I read is that ISPs don't like spoofing, and that can affect deliverability or the 'rating' of us as an email sender. 

Does anyone have real insight to what is best practice and what ISPs really look at? 


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Re: Best Practices: Spoofing the Sender
« Reply #1 on: April 15, 2010, 02:02:42 PM »

It may help if you clarify what you mean by the sender.  Are you talking about the From: header address, or are you talking about the Sender: header address?  Possibly the SMTP MAIL FROM command address?

In general, most service providers send email using the customer's domain in the From: address.  As long as your customer's authentication records are correct for this domain (senderID, SPF, DK/DKIM), then this is not an issue and not itself necessarily frowned upon.  It can be problematic however getting your customer to change their DNS records.

The Sender: header seems like the right solution for service providers, since this domain takes priority for checking authentication records, however it creates the phrase "On behalf of...." in Outlook and other clients, which is usually a deterrent for senders.



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  • Hasan Kurtoglu
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Re: Best Practices: Spoofing the Sender
« Reply #2 on: April 22, 2010, 05:40:25 PM »

You better use the real mail from.
ISPs dont like spoofing.

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