Josetta wrote:

I autoforward emails that I get from a specific client to one of my
users, but I also send regular emails that are not autoforwarded to
him.

In order to distinguish the ones that are autoforwarded, I want to be
able to flag (on his machine) those messages after they arrive.
There is a field called Auto Forwarded and that is checked, so I want
to be able to check that field when the email arrives and if Auto
Forwarded is true, then flag it.

I don't believe you can affect the flag attribute of the message in his mail
client.
--
Brian Tillman [MVP-Outlook]