Outlook generally strips any categories (keywords) on a message before it
goes out and if still there when it arrives.
The DASL tag urn:schemas:mailheader:keywords is used for Keywords
(categories) as a MAPI property, but as I said that's usually stripped out
from outgoing and incoming messages. In fact, Outlook 2007 has a default
rule to strip categories from mail as it arrives.
So if that tag in the Internet headers is there when the item goes out it
probably won't be there in most cases when you examine it.

Signature
Ken Slovak
[MVP - Outlook]
http://www.slovaktech.com
Author: Professional Programming Outlook 2007
Reminder Manager, Extended Reminders, Attachment Options
http://www.slovaktech.com/products.htm
> Hello,
>
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>
> Thanks in advance.