Issue installing Kaspersky Endpoint Security for Windows on top of Kaspersky Security for Windows Server

The article concerns:

• Kaspersky Endpoint Security 11.9.0 for Windows (version 11.9.0.351)
• Kaspersky Endpoint Security 11.8.0 for Windows (version 11.8.0.384)
• Kaspersky Endpoint Security 11.7.0 for Windows (version 11.7.0.669)
• Kaspersky Endpoint Security 11.6.0 for Windows (version 11.6.0.394)
• Kaspersky Endpoint Security 11.5.0 for Windows (version 11.5.0.590)
• Kaspersky Endpoint Security 11.4.0 for Windows (version 11.4.0.233)
• Kaspersky Endpoint Security 11.3.0 for Windows (version 11.3.0.773)
• Kaspersky Endpoint Security 11.2.0 for Windows (version 11.2.0.2254)

Issue

When installing Kaspersky Endpoint Security for Windows version 11.9.0 and earlier on servers with Kaspersky Security for Windows Server installed, you may encounter errors booting the operating system.

Cause

The issue is caused by incorrect removal of Kaspersky Security for Windows Server, due to which active drivers of Kaspersky Security for Windows Server may remain in the system and conflict with Kaspersky Endpoint Security for Windows.

Solution

1. Boot the computer in Safe Mode. For instructions, see this article. 
2. Uninstall Kaspersky Security for Windows Server and check if it was deleted correctly. For instructions, see Online Help. 
3. Boot the computer in the regular mode and check if Kaspersky Endpoint Security for Windows works correctly. If the application won't start, reinstall it.

To avoid this issue, we recommend the following:

• Use Kaspersky Endpoint Security for Windows version 11.10.0 and later for upgrading Kaspersky Security for Windows Server.
• Fully remove Kaspersky Security для Windows Server before installing Kaspersky Endpoint Security for Windows version 11.9.0 or earlier. For instructions, see Online Help.

What to do if the solution did not help

If the issue persists, send a request to Kaspersky support via Kaspersky CompanyAccount with a detailed description of the problem. Before contacting the support, see the following section of the Knowledge Base.