Wednesday, May 27, 2015

Forticlient VPN SSL Stops at 40%




It is very strange your computer can not manage login to VPN via forticlient. you try connect to VPN SSL Fortigate and stop at 40% , and come out message error "Unable to establish the VPN connection. The VPN server may be unreachable (-5)".

There is two ways fix this problem. 


    Change your MTU interface computer via command prompt
      • Click the "Windows Button" on the task bar.
      • Click "All Programs".
      • Click "Accessories".
      • Right Click on "Command Prompt" then click "Run as adminstrator".
      • Then type "netsh interface ipv4 show subinterface".
      • Press Enter
              you will see a list of network interface

              Note :
    • If your connection using wireless then change MTU on "Wirelless Network Connection"
    • If you connection using cable then change MTU on "Local Area Network"

      • Type "netsh interface ip4 set subinterface wireless network connection mtu=1300 store=persistent"
      •  Press Enter and restart your computer
      Change your interface MTU computer using Register Editor
        • Open regedit as an administrator account
        • Navigate to HKLM\System\CurrentControlSet\Services\tcpip\parameters\interface\[Choose the interface in the question] (Do this by checking the correct IP address is in the setting under this key for the adapter you are configuring)
        • Once your are in the correct key for your interface, right-click and select new DWORD value (32bit)
        • Call it MTU
        • Change the Hexadecimal value equal to the setting 514
        •  Close the Register Editor window and restart your computer

      Now you able to login VPN SSL Fortigate without any problem.