I've got our in-house SV9100 running with a dozen IP phones on our LAN, everything been working great for a few weeks. Now I'm trying to add a remote IP phone and am having all kinds of trouble.

I've narrowed it down to when I assign our routers WAN IP (public IP) to 10-12-07 'NAPT Router IP Address' for some reason this causes the inside phones on the LAN to loose connection with the 9100. If I set 10-12-07 back to default 0.0.0.0 the phones reconnect and all's well.

Why does this affect the phones on the LAN?

It shouldn't. Never seen that before. Do you have your internal phones setup correctly?

I got it working, watching the training video for SL2100 remote IP helped, same steps...

I had to add the local area network to 10-58 (networks to exclude from NAT). I also forgot to set all IP phone for NAT plug-and-play in 15-05. Not sure why the phones on the same LAN as the SV9100 would be set for NAT plug/play but its working. Now the local phones are ok and the remote IPT registered and works.

10-58 for whatever reason by NEC should be set with all 3 network types as standard. No idea why they ship that way.