How can I prove him wrong? I know that there are SFP records out there for our email domain. (Mail.ourdomain.com) 220.127.116.11 but the information that the recipient is providign to us shows that SPF lookup is failing on mailsweeper6.ourdomain.org which is our mailsweeper appliance. Why is his SPF lookup looking at this internal address?
The recipients IT staff (Hosted email by DNSPark) keeps thrwoing it back in our lap saying the problem is on our end. I am not quite sure what tool I can use to prove that a SPF lookup on our mail domain is valid. I also don't understand why they are doing a lookup on the server name of our mime sweeper box?
The recipient's IT department replies with:
" The sending server admin needs to ensure that their sending IP/host is listed in the SPF record for whatever domain is used to send mail. That is the quickest route to resolution of this issue."