On 2011-05-30 10:44 AM, Steve wrote:
> Corporation A)  Backup software sends to IT who has their email hosted at
> GoDaddy. 
> Corporation B) Backup software sends log to same IT server at Godaddy. 
> 
> Corp A) doesn't go through.  Corp B) goes through perfectly fine.  
> 
> Both relay through our server.  Both with same destination.  That is the odd
> part.  
> 

There is nothing odd here at all. As Lyle said in his email:

Corporation A) has their own DNS records with an SPF entry that DOES NOT
include the IP address of your server.

Corporation B) has their own DNS records with either:
1) no SPF records at all
2) an SPF record that includes your server's IP address

In the case of Corp A), the final receiving server looks at Corp A)'s
DNS records and finds that you are not authorized to send mail for them
per SPF.

In the case of Corp B), the final receiving server looks at Corp B)'s
DNS records and finds either that you ARE authorized to send mail for
them per SPF or there is no SPF record at all, so it drops the check and
accepts the mail.

-- 
Neil Herber