I have a new install of Zimbra, and it is working just fine, except for the forwarding. I have a few users who I simply relay mail to. I setup their accounts with a forwarding address, and checked the "Don't keep a local copy of messages" box, but they weren't getting email forwarded. If I uncheck that box, they receive mail in their inbox, so I know incoming is working correctly. Also, I can send email from zimbra to the forwarded address from my account, so I also know that that server can send to that email address. It is just the forwarding that isn't working.