You could also try exim or sendmail, but I have much less experience with those. Postfix really isn't that hard: here is a good tutorial for your use case: knowplace.org - SMTP Gateway for Multiple...

It should, but it isn't. The cause is your account is identified by the "ID", and not by email-address.

I just figured this out too, after having migrated all accounts to a new server, which...

In your first post you mentioned it was going to be the same server, hence my suggestion of simply "upgrading" to ZCS 8 NE on this same server.

If you're moving servers I'd suggest you install NE...

If I'm not mistaken... you can simply install ZCS 8.0 NE the same way as if it were a version update (to e.g. 8.0.1). Not 100% sure about ZCS 8, but I'm sure this was the case with ZCS 6. It will...

I think you have set the rest_request_max_upload_size too low, 2800000000 bytes is only ~2.6 GB, and quite close to the mailbox size of 2.5 GB. Depending on your filesystem, blocksize etc. this may...

Reading the postfix documentation on transport tables will be a good start. Add a google search for "postfix mail routing" and I'm sure you'll manage to set it up ;)

There's a manual for creating...

I'd put a small Postfix server before the two (open-source) Zimbra VM's, routing Domain1 to Server1 and Domain2 to Server2.

We did that a while ago while migrating one domain at a time from a...

Not sure about Tasks, but Contacts are accessible via CardDav and Calendars via iCal / CalDav. Many desktop clients support this, but since I've had the pleasure of saying goodbye to Outlook a long...