

ZCO is only available for Outlook running on Windows systems. The Zimbra Connector for Microsoft Outlook (ZCO) provides real time two-way synchronization of mail, contacts, tasks, and calendar between Outlook and the Zimbra server.Not all users are able to understand the complicated interface of Zimbra as not all users are from the Technical background. When the file becomes corrupt and damaged. When the files exceed the file size limitation, then they prefer to opt for a Zimbra to PST converter to export Zimbra to Outlook. With Powershell skills and the Exchange Console you can basically forget about the GUI.When the user wants to export their data to a particular format, then they move the TGZ files to Outlook.

I'm not sure how much you know about Exchange 07 but compared to 03, it's a completely different animal. You have to do it from the Exchange console which is fine but there are little caveats in the setting of permissions that are pretty annoying. Only thing I hate about 07 is the administration of Public Folders. I agree the web portion is fantastic but if you users are tied to outlook, Exchange 2007 is the way to go hands down. It didn't tie into active directory very easily, there wasn't any mobile functionality, and it was a pain in the ass to setup properly. Restoring a single piece of mail to a user's inbox wasn't possible. Zimbra didn't have a journaling system when we used it 3 years ago (not sure if it does now) and backup and restore was hit or miss.

User's also bitched about the nerfed calendar functionality in outlook until they were blue in the face and there were tons of other problems with the client. Our experience as well when we demo'd Zimbra wasn't very good. Exchange can be a pain to administer but your users will appreciate not having to deal with even more bugs in outlook. Of course all this information is based my experiences from a few years ago but I'm of the opinion that if you're trying to get outlook to play nice with a messenging server, microsoft is going to know its own product the best and have the best integration.

I really loved the webmail portion and the integration with basic standards (IMAP, POP, etc) was just fine. Outside the exchange eviroment it was great. A lot of normal exchange like functionality in Zimbra wasn't available and the functionality they did have was buggy. The main issue was that the vast majority of our users used Outlook and the outlook plugin didn't function very well. We ended up moving to exchange after 6 months on Zimbra. This was about 3 years ago so I imagine things have changed but our experience was not positive. A company I use to work for migrated from Qmail to Zimbra.
