When you reply to a message or forward a message by using a Microsoft Office Outlook client in a Microsoft Exchange Server 2007 Service Pack 1 (SP1), Exchange Server 2010, or Exchange Server 2010 Service Pack 1 (SP1) environment, Japanese DBCS characters that appear in any of the following fields become corrupt:
The display name of the sender
The display name of the recipients
The file name of an attachment
The message body
This problem occurs if the field contains one byte Kana.
The problem also occurs if the message is sent by Outlook Web Access (OWA) in an Exchange Server 2007 SP1, Exchange Server 2010, or Exchange Server 2010 SP1 environment.
Note This article does not list all conditions under which this problem may occur.
To resolve this issue, follow these steps:
Install the latest Update Rollup or Service Pack for Exchange 2007 SP1.
For more information about how to obtain the latest Exchange service pack or update rollup, go to the following Microsoft website:
If this line does not exist between the <appsettings> tag and the </appsettings> tag, insert this line.
If you set the value of the PreferredInternetCodePageForShiftJIS key to 50222, this problem occurs.
Save the changes, and then exit Notepad.
Restart the Exchange Transport service.
The resolution above modifying EdgeTransport.exe.config XML prevents the Exchange Transport service from stamping messages with a value of 50222.
In Exchange Server 2010 SP1 or SP2, the same problem can still occur because of Exchange RPC Client Access service or Outlook Web App(OWA) stamps messages with a value of 50222. For more information, see the following Microsoft Knowledge Base article:
2642153 Japanese DBCS characters are corrupted when you reply to a message or forward a message
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.