Thank you for your help, I am running IE 10 with Active X allowed and I have tried Firefox 24 with Java 7 update 40.
Not sure if this helps but this is my httpd.log file from when I connect with Firefox:
Sep 19 15:21:10 CORP-SRH clear-log[6453]: logfile cleared
httpd: 2: GET / HTTP/1.1
httpd: 0: jauth modifyJuniperRequests /
httpd: 2: CheckInterface called
httpd: 2: redirectInterface called
httpd: 0: URI token is NULL
httpd: 0: Interface allowed for dvpn URL. Transparent redirect to /dynamic-vpn
httpd: 2: redirectUri called
httpd: 2: DEBUG: redirectCallback /dynamic-vpn
httpd: 2: GET /dynamic-vpn/login.php HTTP/1.1
httpd: 0: jauth modifyJuniperRequests /dynamic-vpn/login.php
httpd: 2: CheckInterface called
httpd: 2: redirectInterface called
httpd: 2: redirectUri called
httpd: 2: CreateMGD: sendmsg to gk for url /dynamic-vpn/login.php
httpd: 2: Matched Dynamic VPN URL /dynamic-vpn/login.php
httpd: 2: requestCompleted : Closing gk fd 15 for URL /dynamic-vpn/login.php
httpd: 2: POST /dynamic-vpn/login HTTP/1.1
httpd: 0: jauth modifyJuniperRequests /dynamic-vpn/login
httpd: 2: CheckInterface called
httpd: 2: redirectInterface called
httpd: 2: redirectUri called
httpd: 2: CreateMGD: sendmsg to gk for url /dynamic-vpn/login.php
httpd: 2: Matched Dynamic VPN URL /dynamic-vpn/login.php
httpd: 2: Matched Dynamic VPN URL /dynamic-vpn/login.php
httpd: 2: DEBUG: redirectCallback /dynamic-vpn/login.php
httpd: 2: requestCompleted : Closing gk fd 15 for URL /dynamic-vpn/login.php
httpd: 2: GET /dynamic-vpn/setup.php HTTP/1.1
httpd: 0: jauth modifyJuniperRequests /dynamic-vpn/setup.php
httpd: 2: CheckInterface called
httpd: 2: redirectInterface called
httpd: 2: redirectUri called
httpd: 2: CreateMGD: sendmsg to gk for url /dynamic-vpn/setup.php
httpd: 2: Matched Dynamic VPN URL /dynamic-vpn/setup.php
httpd: 2: DEBUG: redirectCallback /dynamic-vpn/setup.php
httpd: 2: requestCompleted : Closing gk fd 15 for URL /dynamic-vpn/setup.php
httpd: 2: GET /dynamic-vpn/login.php HTTP/1.1
httpd: 0: jauth modifyJuniperRequests /dynamic-vpn/login.php
httpd: 2: CheckInterface called
httpd: 2: redirectInterface called
httpd: 2: redirectUri called
httpd: 2: CreateMGD: sendmsg to gk for url /dynamic-vpn/login.php
httpd: 2: Matched Dynamic VPN URL /dynamic-vpn/login.php
httpd: 2: requestCompleted : Closing gk fd 15 for URL /dynamic-vpn/login.php