SPF/origination details needed for e-mailed receipts from Authorize.net

[karenb]

When we use the receipt option in which Authorize.net e-mails the receipt to the customer and our e-mail address is inserted by Authorize.net as the sender of the e-mail even though Authorize.net is the actual originator of the e-mail, we need to know the exact and complete list of Authorize.net domain names and/or IP addresses from which Authorize.net will actually be sending the receipt e-mails so that these Authorize.net domains/IPs can be whitelisted in our SPF records to help confirm the authenticity of the e-mails.  Where can we find this information, or is the originator guaranteed to always simply be "authorize.net"?

[RichardH]

Hello @karenb 

Emails sent to Merchants and Customers from Authorize.Net originate from 64.94.119.16, and 64.94.119.17.

Richard

[StAlphonzo]

Hi, I hope it's okay to post this question here. We support a client who uses authorize.net and Office 365 as their email service. 

We've added the IPs you noted above but we're still receiving bounce messages when authorize.net attempts to email a receipt to a customer. 

Here is the SPF record we're using: 

v=spf1 include:spf.protection.outlook.com ip4:64.94.119.16 ip4:64.94.119.17 -all

Are there other IPs authorize.net sends from? Have they changed recently? Thanks in advance for a reponse.