HỖ TRỢ ⚠️ This will disconnect active VPN users temporarily.
: Before running the installer, right-click the .exe installation file, select Properties, and in the General tab, check the “Unblock” option if present. This prevents Windows from blocking the installer due to security restrictions from downloaded files.
ping vpn.yourcompany.com
Windows User Account Control (UAC) sometimes restricts installer actions silently without throwing an explicit permission prompt. Locate the downloaded .exe or .msi Kerio installer file. Right-click the file and select .
If network connectivity is confirmed, the next suspect is a . Kerio Control updates often refine the VPN handshake. A client version 9.x attempting to connect to a server version 8.x may trigger Error 28201 because the cryptographic handshake fails. To resolve this, ensure both the client and server are updated to the latest compatible versions (e.g., both on the same major release). In some cases, the server configuration may have "Allow only secure ciphers" enabled, which the client cannot negotiate. The solution is to temporarily relax cipher requirements on the server for testing, then update the client. error 28201 kerio vpn client
Below are the most effective methods to resolve the issue, moving from simple to more complex procedures.
Go to Control Panel > Programs and Features and uninstall the Kerio VPN client. ⚠️ This will disconnect active VPN users temporarily
Depending on your Windows configuration, Error 28201 will output specific hexadecimal results:
VPN Client error 28201 (Often accompanied by "Connection failed" or "Unable to establish VPN tunnel") ping vpn
Right-click and select Uninstall device . Ensure you check the box that says "Attempt to remove the driver for this device" if prompted. Press Win + R , type regedit , and hit Enter. Back up your registry first ( File > Export ).
To fix the "device is already registered" error, you must manually clean up remnants of the old driver.