Zimbra Desktop depends on the Java 6 runtime environment and that is not installed on El Capitan by default. To fix this, follow this link: https://support.apple.com/kb/DL1572?locale=en_US, download and install the Java software. Zimbra Desktop will run after the additional Java version is installed.

Use Outlook's Recover Deleted Items option to restore deleted items. Select the Deleted Items folder. Ensure the item(s) you're looking for is not in the Deleted Items folder. Select the Folder ribbon tab > Recover Deleted Items from Server. Select the items you want to restore and click Recover Sel...

Step 1. Download and Install Outlook Export Software in your computer Step 2. Click on the “Add File or Add Folder” option to load PST files/folder for conversion to the TGZ file format. Step 3. After loading PST files, you get a smart “Preview “option. With this option you can view selected PST fil...

I am facing this error while migrating my Zimbra data to office 365. 1-1-2020 12:17:51 [5652]: (MI): Batch Added Message rid(0) 1-1-2020 12:17:51 [5652]: (MI): Adding Appoinment d(Wed, 8 Mar 2006 14:31:40 -0000) fid(010) 1-1-2020 12:17:51 [5652]: Unable to process message d(Wed, 8 Mar 2006 14:31:40...

What kind of SMTP error you are receiving? There are various SMTP series like 4xx and 5xx error codes. Please provide some more details.
Regards,
Lewis

1. In the ZWC, click the dropdown menu next to your name in the upper right of the screen. 2.Select Offline Mode. 3. In the Offline Mode dialog, select Allow offline mode and click OK. 4. Accept the warning that displays asking if you want to reload the application now to enable offline access? Clic...

There are various 3rd party tools available in the market. They can help you. BUt they are paid tools. Also, you can contact the Zimbra support team for assistance. They can help you with the exact solution.
Regards,
Lewis

You can provision up to 500 accounts on once using the Bulk Account Wizard from the administration console.

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Lewis

Have you tried connecting with the support team? They can help you with exact solution.
Regards,
Lewis