Hi

I appreciate that this will be somewhat difficult to diagnose, since only I am able to see the network...but here goes.

I currently have a setup across a large, old - in - parts care home with M5s, connected to a non-TPL router. The main unit plus the others are all showing solid green, and connections appear fine with doing an airport utility scan test - showing that at all times they are no less than say -55 to -60dBm. The base is on the ground floor, along with three of the other m5s. There is one almost directly above one of these on the first floor, and I am trying to connect another in a similar position upstairs further along the corridor. However, I have tried so many times without success to connect an additional unit within approx 10 - 15 metres along this narrow, but unobstructed corridor to the last one 'in the chain', as it were. Even if I move it to say 2m away, and with no physical obstruction, it just refuses to connect properly. I *think* it once got to the solid blue stage, but even if I connected it elsewhere, got the green light and then tried to move it back to this position 2m from the last unit (which is solid green, even after a reboot), the new unit does not find the network and remains flashing amber / red. 

In this 2m example, it is literally a case of one unit being in a corridor, and the 'malfunctioning' one being on a chair, by the open door, right next to the unit in the corridor and with an unobstructed view of them both. I have tried rebooting the entire system, including the master deco and the DHCP controlling router, to no avail. Also, the fact that if the unit is placed elsewhere it connects, seems to suggest not an internal config issue. I therefore have questions:

- just how much does the orientation of the unit (ie flat, or flat against a wall etc) affect transmission? Are they always supposed to be flat? It's worth mentioning that both of the units described above are flat, whereas others in the config are flat against a wall as high as possible;

- what strange factors have people found that prevent devices that should be close enough to each other to connect?

- I have tried different, unused devices in the assumption that maybe I had a defective unit, but it seemed to do the same with this one, too. I am leaning towards some kind of signal blocking, linking to my second question, but I am completely stumped;

- I note that the Decos can handle up to 100 devices, but is that in total or just per individual unit?

- If I were to hard-wire the two devices described here with LAN cable, would the setup be able to use this to establish the connection and allow me to move along to the next area?

Please help!

Thanks

Ant