I'm using 4.1 SP5.... XP Pro PC to Draytek router to Broadband connection.
When I'm using my wireless network card (Edimax) and the secureclient is loaded on that adapter I cannot access the internet or site. Remove the secureclient from the adapter and I can access the internet again (but obviously can't access the site as secureclient isn't loaded now)
However if I bypass the wireless connection and connect directly to my router with a normal NIC and cable it works fine. No problems. Connects to Site and also internet etc.
So there appears to be a problem with the Wireless network card set up.