Unable to Download Mails in Entourage which has “+” in the subject line. Eg. Test + Mail

This happens on both Entourage 2004 and 2008 when you are running Exchange 2007  Sp1 on Windows 2008 Machine which has IIS 7.

To fix this, log into Exchange 2007 Mailbox servers and Client Access server and Mailbox Server and enter the below line in the command prompt. No need for restarting of machine is required.

%windir%\system32\inetsrv\appcmd set config “http://localhost/Exchange” -section:system.webServer/security/requestfiltering -allowDoubleEscaping:true /commit:apphost

You will see the following response after running the above command in the same window.

Applied configuration changes to section “system.webServer/security/requestFiltering” for “MACHINE/WEBROOT/APPHOST/Default Web Site/Exchange” at configuration commit path “MACHINE/WEBROOT/APPHOST”

SOURCE :

http://blogs.technet.com/amir/archive/2008/08/06/e-mail-download-issue-in-entourage-with-exchange-2007-on-windows-2008.aspx