5.7.1 smtp; 550 5.7.1 Message rejected as spam by Content Filtering.

Problem:
A third party daily report has been configured to send to a customer and it has been rejected by customer's Exchange server 2007 (sp3) with below error:
#5.7.1 smtp; 550 5.7.1 Message rejected as spam by Content Filtering.

Research:
An useful discussion:
http://www.experts-exchange.com/Software/Server_Software/Email_Servers/Exchange/Q_24442455.html

Solution:
How to Specify Recipient and Sender Exceptions for Content Filtering
http://technet.microsoft.com/en-us/library/aa995952.aspx

Use Exchange shell to make some change on the server:

1.Added recipient's email to the recipients exception list of content filter
Set-ContentFilterConfig -BypassedRecipients tiffany@contoso.com

2.Added domain examplesender to the allow list.
Set-ContentFilterConfig -BypassedSenderDomains examplesender.com

3.Added the sender email  to the allow list.
Set-ContentFilterConfig -BypassedSenders someone@examplesender.com

Another thing worth to try is to use Exchange console to add  the daily report title as the keyword of  content filter exception