Article ID: 2394554 - View products that this article applies to.
Consider the following scenario:
This issue occurs because Exchange Server 2010 does not process an email message if the subject line contains unsupported encoded characters. Additionally, an exception occurs when Exchange Server 2010 tries to generate a NDR message.
To resolve this issue, install the following update rollup:
(https://support.microsoft.com/kb/2579150/ )Description of Update Rollup 4 for Exchange Server 2010 Service Pack 1
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Article ID: 2394554 - Last Review: July 28, 2011 - Revision: 4.0