Overview

While attempting to start Kerio Connect Antivirus and Anti-spam, the modules are facing issues generating the following errors:

AntivirusModule.cpp: Antivirus update failed: Cannot find update location: The requested URL returned error: 407. Download failed.

BitDefenderAntispamClient.cpp: Unable to initialize Kerio Anti-spam plugin, error: Kerio Anti-spam plugin cannot update: Unable to fetch updates: CouldNotLogin (-2103)

SpamClientBase.cpp: Server: Kerio Anti-spam plugin cannot be initialized: Kerio Anti-spam plugin cannot update: Unable to fetch updates: CouldNotLogin (-2103).

Prerequisites

Administrator access to Kerio Connect server

Diagnosis

The Antivirus and Anti-spam plugins cannot find the updates' server and cannot proceed with downloading the necessary packages. There is a middleware device or software in between Kerio Connect local server and Kerio Connect main server which supply the Antivirus Database definition updates. Common devices/software include proxy servers configured in Kerio Connect Webadmin, firewalls, 3-rd party Antivirus software enabled on local Kerio Connect installation.

Solution

1. Login to Kerio Connect Administration -> Configuration -> Advanced Options -> HTTP Proxy tab -> make sure the proxy configuration is disabled.
   
2. Check the HTTPS connection (port 443) between your Kerio Connect server and Kerio updates servers. You should see the following.
   1. bdupdate.kerio.com
      
   2. update.kerio.com
      
      Important: if the connection is blocked, the webpages will return Connection Timeout responses or similar.
      Note: if you have Kerio Control as the firewall, for more information please refer to configure the firewall to allow Kerio Connect services.
3. Make sure necessary Kerio Connect folders are excluded from the 3-rd party Antivirus scanning. For more information, please refer to Antivirus Exclusions for Kerio Connect.

Confirmation

 The Antivirus and Anti-spam modules are functioning properly, no errors reported in the logs.