The support page for the 3 home signal (which is also made by Cisco AIUI, and probably uses the same hardware inside a different box) says that a constant red light means a problem with the ethernet cable. Have you tried another cable and/or another port on your router?

I did try another port... Will try another cable but it did work before and the device doesn't get moved.

I also tried resetting the router.

Devon - I held the reset button down for well over a minute.

Do you have any NAT involved? - ours worked fine until EE changed something then it went solid red.

Ended up moving it to a different network before it worked (was on a 10.x.x.x network was moved to a 192.168.y.x network - I wonder if EE's internal network is a 10.x.x.x one?)

Hmm... I have not configured any NAT for it -

Router is on 192.168.0.1, addresses are allocated in the 192.168.0.x range. Signal box connected directly to one of the LAN ports on the ADSL router. There's no other infrastructure involved, except a WiFi access point connected on another port with the address 192.168.0.254 (DHCP controlled by the main router, it's only an access point, no routing).

It did not require any further configuration before, do I need to open some ports for it? I'm not sure it's even showing as connected at the moment

I've not had to open any ports for ours. Whenever I've had problems our account manager keeps pressing stuff until we get escalated to Level 2 who actually get them working...

Second time lucky! The first CS guy was obviously on his toes as he didn't fully finish the activation before asking where it's come from and refusing to activate a second hand box. So I decided to be cheeky and just phone through a second time and make sure the voice answering the call was different.... got it activated no problem...

Curious how it knows where it is and whether it can connect though - we have a dynamic IP address so I'm hoping it's not a matter of going through all this every time it changes!

I noticed an EE signal box for pretty cheap in a cash converters recently. I almost considered buying it just to use as a paperweight even if they wouldn't activate it

Having a dynamic IP shouldn't make a difference. Bear in mind that nearly all of the signal box users will be on connections with dynamic IPs, it'd be an amazing oversight if the system was not designed with that in mind

I believe the Vodafone version (mine was made by Sagem) has a receiver that can check the cell IDs that are nearby, if any. I'm not sure what the 3/EE version (made by Cisco) has. EE may well be using some sort of geo-IP system to further limit the ability of the box to fire itself up while abroad though.

True enough! Makes sense on the cell ID thing.

Just toggled the power out of interest, it took a few minutes (gulp) but connected back in again so still looking good

Looking at the small print, I can see where they're coming from as actually the box is still technically theirs. If they were really nasty about it they could probably come down pretty hard on people for selling their equipment Good thing they're nice.