This is weird, If a user sends an email internally (either new or forwarded) the email history disappears.
For Example:
If I send you an email, when you reply your original email is included within the reply, then if I reply to you the two original emails are within my reply.
These are all removed (or more precisely not displayed) if the recipient is an internal client. But they are displayed if the recipient is an external email address.
I have checked and all the clients have the “include original email text” setting set in \tools\preferences\email options\on replies and forwards in Outlook. It must be something within Exchange that is not displaying the email history because if you, as the recipient of an email with no history forwards it to me saying “look here is an example of an email with no history” it arrives complete with history. One other clue if you check the senders “Sent Items” the history is missing.
All clients are using Outlook 2003 with all latest patches.