We have presently hooked up about 60 users to our Zimbra server, and all of them use Thunderbird. I am considering a move from Thunderbird to Zimbra Desktop. But, having tried Zimbra Desktop for myself, I am unsure if this is feasible. Here are my points:
* For one, various workflows in our firm are based on "redirecting" individual messages: When Paul receives a message from John, but that message should be handled by Mary, Paul redirects the message to Mary, i.e. he sends the message to Mary, but its sender remains John, so when Mary replies, the reply goes to John, not Paul. I have not seen a way to do that in Zimbra Desktop.
* Our users are writing messages in German and English on a regular basis, and they should therefore be able to switch the language of the spellchecker quickly and easily. The Zimbra Desktop client I have downloaded happily spellchecks in English, but I have not found a way to switch to another language.
* A small group of our users must be able to send/recieve S/MIME-encrypted mail. I know that Zimbra 7.1 does provide some support for this, but I have not found any information if Zimbra Desktop will as well.
I like Zimbra Desktop, but unless I find a way to resolve at least the first two points, I will not be able to switch our users over. Did I overlook anything?