Thank you for the advise on fixing the null_sender header which gave an error in the Exchange server event viewer.
You suggested : "Just add "null_sender=" (empty null sender) to the pipe(8) transport
in question. If you need a Return-Path,
make sure "R" is present in "flags", otherwise just leave "R" out. If
you want to not have "<MAILER-DAEMON>" as the the Return-Path: specify
a better "null_sender", the best value is generally empty."
After logging in as root, I changed the directory with the comand: cd /etc/postfix/
Then went to the master.cf with the command: mc -e master.cf
Then I went to the bsmtp flag and removed the "R". I have been testing to see if there were any header errors in the Exchange event viewer and am happy everything is working fine.