One of the annoyances that we run into after installing Microsoft Dyanamics CRM 4.0 was receiving the following dialog box when trying to track an e-mail. I’ve done searches for the past that hadn’t run across anything until today.
It turns out, that the length of the ‘messageid’ attribute in the e-mail entity is set to 100 and occasionally the message ID of the message can be longer, which causes this message. If you change the maximum length of the messageID attribute in the e-mail entity to 200, this should solve the problem
Find the detailed solution here: http://www.sadev.co.za/node/160.
Thanks to rmaclean’s blog for the answer