While having problems with Outlook, until they’re resolved, we recommend using the web client. For instance if you're using zMailCloud, login at https://yourdomain.zmailcloud.com
First, verify your Windows operating system (OS), Zimbra Connector for Outlook (ZCO), and Outlook application (mail client) are up to date.
You may download the latest Zimbra connector for your computer (unsigned, try 64-bit first if you're unsure. If you can't use the 64-bit, it may be time to upgrade your computer itself).
All installations of Microsoft Outlook must be 2013 or later, and both Outlook and Microsoft Office must have the latest updates from Microsoft.
Note if Outlook is upgraded to a different version, the connector must be uninstalled and reinstalled. This is particularly important following an upgrade to Outlook 2013, as the connector needs to be installed to a different location on your computer
Verify your Outlook isn’t running any other plugins other than the ZCO. Disable your Kaspersky plug-in, and any other anti-virus/spam or firewall features that may interfere. It is not uncommon for ZCO to encounter problems when running third-party Outlook add-ins or antivirus software. Try disabling the add-ins before retrying to use ZCO.
Given all that’s good…
Repairing ZCO
1. Locate the ZCO MSI used to install ZCO and download the file to your computer.
To find out which version of ZCO is installed, open Outlook and go to: Zimbra Ribbon > About Zimbra.
Click the file to open. When the MSI is run when ZCO is already installed, it opens with the options to repair the connector.
Click repair. ZCO is reinstalled.
If none of that helps, please try deleting and re-installing the profile.
Other specific problems and solutions:
Unable to Access a Shared Item
Verify that the user has accessed the calendar correctly:
a. Open > File > Other User’s Mailbox. The Global Address Book is displayed.
b. Select the sharing user from the list. The shared item should sync automatically.
The .zdb File is Corrupt
A user receives a Local Failure message stating that the .zdb file is corrupt. To fix this issue, you must repair the .zdb file. The .zdb file includes all Outlook data from Zimbra Collaboration in .pst format: messages, contacts, appointments, tasks, etc.
Use the scanpst.exe tool to repair any .zdb file that Outlook/ZCO has trouble opening.
General reference
Includes advanced troubleshooting options that may not be supporting by Cloudiance, use at your own risk: https://wiki.zimbra.com/wiki/Category:ZCO
