I thank you gain for your help, but that does not appear to match my tests. I have 3 Accounts. at least 98% of all my mail is sent directly to one of these accounts. They come in to 3 different PSTs, but after receipt I move them around to either a 4th "temp" pst or to my main pst. In the outlook explorer window I can add a column "E-mail Account" and it shows the name of the account the item was originally received by. If I hit reply the sending account is the always the account through which the item was originally received. As noted, I am sure that very few of these were received through any forwarding process. I have tested the script on a large number of items -- in each of the psts, and from each of the accounts. "Msgbox mail.sender" always verifies that I am seeing the correct item, but "MsgBox Mail.Fields(PR_NEXT_SENDING_ACCOUNT)(PR_NEXT_SENDING_ACCOUNT)" continues to show blank.