As a user, you can change how Horizon Client handles certificate checking. A certificate is a digital form of identification, similar to a passport or a driver's license. Server certificate checking occurs for connections between Horizon Client and a server. If you are unable to change modes, check with the administrator who may have deactivated this feature for Horizon Client.


  1. Start Horizon Client.
  2. Click the Settings (gear) icon in the upper-right corner of the Horizon Client window and select SSL Configuration.
  3. Select the certificate checking mode.
    Option Description
    Never connect to untrusted servers This setting means that you cannot connect to the server if any of the certificate checks fail. An error message lists the checks that failed.
    Warn before connecting to untrusted servers This setting means that you can click Continue to ignore the warning if a certificate check fails because the server uses a self-signed certificate. For self-signed certificates, the certificate name is not required to match the server name that you entered in Horizon Client. You can also receive a warning if the certificate has expired.
    Do not verify server identity certificates This setting means that no certificate checking occurs.
  4. (Optional) If your environment includes an SSL proxy server, enable the Thumbprint Verification or PKI Verification option in protocol connection certificate checking mode.
    This setting allows certificate checking for remote desktop and published application connections through an SSL proxy server. You cannot activate this setting if you select Do not verify server identity certificates.

What to do next

If you receive a certificate error after setting the certificate checking mode, contact your system administrator.