Hi,
Was wondering if anyone else has ran into this issue. We have a client that is unable to send mail to anyone hosted on Rackspace. We are running an Exchange 2010 box that forwards outgoing mail through a fortimail unit. Sometimes the mail goes through if it is the first one of the day. I have checked to ensure we are not blacklisted. I have checked to see if Rackspace uses SPF checking they do not. Often we get back #< #4.4.7 SMTP; > #SMTP#. or
I have tried changing the DNS provider that does our look ups, seems I can resolve everything ok. If I punch the domain into mxtoolbox everything looks alright. I can not figure out why Rackspace seems to drop the schefferandrew.com domain. I get no logs other than unable to reach destination in the fortimail logs.
Hoping someone can help me find what to look for.