When a newer version of the ZCO msi file becomes available, you can upload the file to the ZCS server. The new ZCO msi file is uploaded to the /opt/zimbra/jetty/webapps/zimbra/downloads directory.
Download the new ZCO file to a computer that you can access from the administration console.
Go to Tools and Migration > Client Upload.
Click Browse to locate the ZCO file to upload.
Click Upload.
Restart ZCS. Type zmcontrol restart from the command line.
The downloads/index.html file is updated so that the new file can be downloaded from the ZCO link on the administration console Tools and Migration > Download page.
If you do not restart the server, the ZCO download link on the Zimbra Utilities Download page does not select the newer version to download.