Vpn Client - Error 28201 Kerio

~1,600+ words. Optimized for search intent, technical depth, and actionable resolution steps.

No. It occurs on Windows, macOS, and even Linux versions of the Kerio VPN Client, though Windows is most common.

Unable to Install Kerio VPN Client on Windows with Error 28201

Navigate to the following path: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\4d36e972-e325-11ce-bfc1-08002be10318 error 28201 kerio vpn client

Look through the subkeys (numbered 0001 , 0002 , etc.) to find any entry explicitly mentioning . Right-click the specific subkey folder and select Delete .

[ERROR] [VPN] SSL handshake failed: certificate verify failed (error: 28201) [INFO] Server certificate common name does not match requested hostname.

: Download and run the KT Uninstaller utility from GFI/Kerio. This tool specifically targets leftover registry keys and configurations that block new installations. Manual Driver Removal ~1,600+ words

To resolve Error 28201, follow these step-by-step troubleshooting guides:

Follow the registry cleanup and use the Kerio VPN Recovery tool available at Kerio Control GFI Support.

: Starting with Windows 8 and continuing through Windows 10 and Windows 11, Microsoft tightened driver signing requirements. Older Kerio VPN Client versions prior to 9.2.7 use drivers that are not properly signed for modern Windows environments, triggering the installation failure. The Kerio Virtual Network Adapter may show as “Not digitally signed” in its Properties window, which Windows interprets as an invalid and unsafe driver that cannot be installed. It occurs on Windows, macOS, and even Linux

: Kerio regularly updates the VPN client with signed drivers and compatibility fixes. Version 9.2.7 (build 4393) and later contain properly signed drivers for Windows 10 version 20.04 and newer. Installing older versions on modern Windows systems almost guarantees encountering error 28201.

Error 28201. Failed to install VPN device driver. Command: REMOVE. Action: RemoveDevice. Result: 0x800F020B, unspecified error