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. Open the Horizon app.
  2. Tap the Settings (gear) icon in the upper-right corner of the Horizon Client window, tap Security options, and tap Security mode.
  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.

What to do next

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