We started using a third party spam solution ( pointed our MX records to them) and since then some of our e-mails are being rejected by are 2007 in house Exchange server. The exact error is below and shows up on our third party log file. I was told by the spam vendor that I need to turn off SPF checking on our Exchange server.  In EMC at the Organization Config --> Hub Transport --Anti Spam we have Sender ID set to "Stamp message with Sender ID result and continue processing."  Is there another location on Exchange that SPF filtering is enabled? 

SMTP Delivery Result Failure

Connected to XX.XX.XX.XX but recipient was rejected. Remote host said: 550 SPF failure see http://spf.pobox.com/ (#5.7.1)

Thanks,

If all your inbound mail comes from your antispam service, then why don't you just turn off content filtering entirely?

We started using a third party spam solution ( pointed our MX records to them) and since then some of our e-mails are being rejected by are 2007 in house Exchange server. The exact error is below and shows up on our third party log file. I was told by the spam vendor that I need to turn off SPF checking on our Exchange server.  In EMC at the Organization Config --> Hub Transport --Anti Spam we have Sender ID set to "Stamp message with Sender ID result and continue processing."  Is there another location on Exchange that SPF filtering is enabled? 

SMTP Delivery Result Failure

Connected to XX.XX.XX.XX but recipient was rejected. Remote host said: 550 SPF failure see http://spf.pobox.com/ (#5.7.1)

Thanks,

Can you not just adjust your SPF records for your domain to include your third-party mail filters relays?