I received 3's Home Signal box a couple of days ago and it hasn't worked at all. The box has a light which is supposed to flash green quickly as it's connecting and then stay steady when connected or flash slowly when data is in use. All I've had from the box is the initial red light when powered on, and then a fast flashing green light which I've now had for 24 hours straight.

I've rebooted the box, changed the ethernet cable, reset the box using a pin, re-inserted the sim card. I've even contacted Three who tell me that on their end, they cannot see the box and it doesn't seem to have contacted their network at all. I've confirmed the IMEI and the sim ID with them, they removed my home signal box from my account and added it again but that didn't help either.

I have forwarded all the ports required on my router and my internet connection is very stable, 160mbps down and 12mpbs up. It's looking like they are going to have to send me a new box, but it seems very strange that this one isn't working at all.

I can see the box in my router settings, I see the mac address and that it's been assigned a local IP, it has internet access that's for sure. I wonder if anyone else has had this issue, have I missed something?

This is the box I've got:
https://www.youtube.com/watch?v=msNZp6wmQUk

Silly as it may sound, try putting the Home Signal in the DMZ on your router, that should me it will be able to get on the internet free of router restrictions.

Might I ask who your broadband provider is?

Also what kind router it is?

I will give DMZ a go, it's an Asus RT-N56U. I'm with Virgin Media, here is a speedtest:
http://www.speedtest.net/my-result/4029348997

Edit: Nope, DMZ has not helped, same issue.

How close is the home signal box to your router? When I first got mine it was a bit picky about interference from the router / wifi so I ran a longer Ethernet cable a couple more meters away and that seemed to help the home signal box establish an initial connection. After that it seemed a little less fussy and I could get away with it being a bit closer.

Moving the box away from my router was one of the suggestions I got from the Three advisor, but it didn't help. I have to say, I had really great service from them, the advisor I spoke to escalated my issue and was prompt with 2 call backs and found out as much information as he could. Unfortunately he couldn't get to the bottom of it even with the network team involved.

I had my Virgin Media router in modem only mode, and was just using my Asus router for all my devices. Ended up enabling the router features on the VM modem and plugging the home signal box into that, and it worked straight away without forwarding any ports or changing any settings at all.

I've never had a problem with any of my wired or wireless devices on my Asus router, and considering I did DMZ the home signal box and it still didn't work, I'm guessing it's some kind of compatibility issue between the home signal box and the router. It works perfectly fine with the VM router, full signal all around the house, I'm impressed with the range.

Well, if anything, hopefully this thread could come in handy for anyone else having a similar issue.