Happy 2015 everybody 
I recently paid for static IP addresses to use on my network. This was to allow several "servers" to be accessible from the internet.
As soon as I did this, the "server" on the new Static IP address became innacessible from devices on the main LAN.
Similarly the "server", now proudly boasting its new static "217.xxx" address, could no longer communicate with devices on the LAN.
By "communicate", I mean that they dissapeared from each others network neighbourhood, could not browse to one anothers shares (even when forced by directly typing the UNC in), nor even PING one another.
This is a BIG deal for me as far as BT is concerned. The server MUST be able to see LAN shares in order to fulfill its backup role.
In addition, a second Static IP device - a hard disk recorder - is pingeable from the internet, but refuses to respond to HTTP calls. (it has a web interface). When I turn the Business Hub 3.0 firewall off, it works. It stops working as soon as the firewall is turned back on. Port forwarding for HTTP and HTTPS has been enabled to the device.
Can anyone offer any advice ?
Configuration summary:
BT HomeHub 3.0
Lan port 1: "Server" - a windows 7 Pro machine with various shares on it. Static IP 217.xxx.yyy.26, as configured through Businesshub 3.0
Lan port 2: The DVR. Static IP 217.xxx.yyy.25, as configured through Business Hub 3.0
Lan port 3: feed to a hub. 192.168.0.X network, as per DHCP settings on Homehub 3.0
Hub - distributs to 5 PC's, all running Windows 7 Pro.
Static IP device unable to communicate with 192.168.x.y devices. (worked previously), even at PING level.