Overview

When using Webmail in different browsers, like Google Chrome, Firefox, or Edge, the UI crashes and stops responding to any action. An unexpected error occurred in Kerio Connect Client failure warning is displayed for no apparent reason.

When clicking on Show Data, the full error is shown:

Cannot read property 'nestingLevel' of undefined

Prerequisites

Administrator (root) access to the Kerio Connect server

Solution

The Development team has identified the Webmail crash issue that is occurring and the next version of Kerio Connect will contain a fix for this.

In the meantime, the hotfix can be deployed to the current Kerio Connect 9.3.0 installations.

1. Download the hotfix file.
2. Extract the ZIP archive.
3. Navigate to the following directory, based on installed OS. Defaults are:
   1. Windows: C:\Program Files\Kerio\MailServer\web\webmail
   2. Linux: /opt/kerio/mailserver/web/webmail
   3. Mac: /usr/local/kerio/mailserver/web/webmail
4. Rename webmail2.js to webmail2.js.bak
   
   
5. Copy the new webmail2.js extracted from the downloaded ZIP archive.
6. Clear Cache on the client browser side to make sure the new webmail2.js is downloaded.
   1. Chrome guide
   2. Firefox guide
   3. Edge guide

Testing

The Webmail is stable and no longer crashing in any mentioned browser.