Web console no longer works in Email Server Security, after installing the security update for Windo

chonch Posts: 10 F-Secure Product Expert


Products affected: Server Security / E-mail and Server Security / PSB Server Security / PSB E-mail and Server Security

Problem: The user cannot open the web console after installing the security update for Windows (KB3061518).

Visible effects: When trying to open the web console, the user receives the following error message: "The page cannot be displayed."

Workaround: After you install this security update, the minimum allowed DHE key length on client computer is changed to 1,024-bit by default, instead of the previous minimum allowed key length of 512-bit.


To resolve the issue:

  1. Download the attached file makecert.zip.
  2. Extract the file and replace makecert.bat in the folder <F-Secure installation folder>\Web Use Interface\bin.
  3. Run makecert.bat from this folder (requires administrator privileges).
  4. Restart the service F-Secure WebUI Daemon (in command prompt: net start f-secure webui daemon).

This replaces the default 512-bit key with a 1,024-bit key.

ETA: Unconfirmed


Fix: To be fixed in the next Server Security release


Internal reference: CTS-96377



  • Peter
    Peter Posts: 186 F-Secure Product Expert



    Starting with Firefox version 39.00, FF displays the following error when accessing the Web Console, unless you have applied the previously described workaround using makecert.bat


    Secure Connection Failed

    An error occurred during a connection to localhost:25023. SSL received a weak ephemeral Diffie-Hellman key in Server Key Exchange handshake message. (Error code: ssl_error_weak_server_ephemeral_dh_key)


    The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.

    Please contact the website owners to inform them of this problem.