We have a sender than cannot send email one of our internal users. We are using IMF Tune from Windeveloper, and their domain is in our permitted sender list and their server IP is in the accepted IP list. This is the only user/domain we're having problems with. Here's an excerpt from our logs, but I'm not sure what else I can permit for them. Thanks for any ideas.
2013-01-10T16:01:38.398Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,2,192.168.24.13:25,216.1.1.1:26336,>,"220 mail.ourdomain.com Microsoft ESMTP MAIL Service ready at Thu, 10 Jan 2013 10:01:37 -0600",
2013-01-10T16:01:38.523Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,3,192.168.24.13:25,216.1.1.1:26336,<,EHLO mail.theirdomain.com,
2013-01-10T16:01:38.523Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,4,192.168.24.13:25,216.1.1.1:26336,>,250-mail.ourdomain.com Hello [216.1.1.1],
2013-01-10T16:01:38.523Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,5,192.168.24.13:25,216.1.1.1:26336,>,250-SIZE 104857600,
2013-01-10T16:01:38.523Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,6,192.168.24.13:25,216.1.1.1:26336,>,250-PIPELINING,
2013-01-10T16:01:38.523Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,7,192.168.24.13:25,216.1.1.1:26336,>,250-DSN,
2013-01-10T16:01:38.523Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,8,192.168.24.13:25,216.1.1.1:26336,>,250-ENHANCEDSTATUSCODES,
2013-01-10T16:01:38.523Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,9,192.168.24.13:25,216.1.1.1:26336,>,250-AUTH,
2013-01-10T16:01:38.523Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,10,192.168.24.13:25,216.1.1.1:26336,>,250-8BITMIME,
2013-01-10T16:01:38.523Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,11,192.168.24.13:25,216.1.1.1:26336,>,250-BINARYMIME,
2013-01-10T16:01:38.523Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,12,192.168.24.13:25,216.1.1.1:26336,>,250 CHUNKING,
2013-01-10T16:01:38.633Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,13,192.168.24.13:25,216.1.1.1:26336,<,MAIL FROM:<Brandi@theirdomain.com> SIZE=5253,
2013-01-10T16:01:38.633Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,14,192.168.24.13:25,216.1.1.1:26336,*,08CF960228587B70;2013-01-10T16:01:38.398Z;1,receiving message
2013-01-10T16:01:38.633Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,15,192.168.24.13:25,216.1.1.1:26336,<,RCPT TO:<nick@ourdomain.com>,
2013-01-10T16:01:38.648Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,16,192.168.24.13:25,216.1.1.1:26336,>,250 2.1.0 Sender OK,
2013-01-10T16:01:38.648Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,17,192.168.24.13:25,216.1.1.1:26336,>,250 2.1.5 Recipient OK,
2013-01-10T16:01:38.773Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,18,192.168.24.13:25,216.1.1.1:26336,<,BDAT 4660 LAST,
2013-01-10T16:01:39.070Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,19,192.168.24.13:25,216.1.1.1:26336,*,Tarpit for '0.00:00:05',
2013-01-10T16:01:44.086Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,20,192.168.24.13:25,216.1.1.1:26336,>,554 5.1.0 Sender denied,
2013-01-10T16:01:44.399Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,21,192.168.24.13:25,216.1.1.1:26336,<,QUIT,
2013-01-10T16:01:44.399Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,22,192.168.24.13:25,216.1.1.1:26336,>,221 2.0.0 Service closing transmission channel,
2013-01-10T16:01:44.399Z,DOLLY\Default SMTP Receive Connector,08CF960228587B70,23,192.168.24.13:25,216.1.1.1:26336,-,,Local