Error “Cannot connect to the application installation source”

Cause

• The PC has a firewall installed that blocks the Internet connection which is required for installation. 
• The operating system has incorrect proxy server settings entered.
• Kaspersky servers are temporarily unavailable due to maintenance.

Solution

• Try to install the application again later (in an hour or so).
• Make sure that a third-party firewall isn’t installed on your computer. The list of incompatible software and the instructions on removing it are available in this article.
• Make sure that Microsoft Defender Firewall doesn’t block the application’s Internet connection. See this article for instructions.
• Reset proxy server settings in the operating system. For details, see this article.
• Try to connect to the Internet using your mobile phone. See the instructions for Android and iOS.
• Change the DNS address in the network settings. See this article for instructions.
• Reset the network settings. For instructions, see this article.

What to do if the error persists

If the issue persists, contact Kaspersky Customer Service.