SSL312 and FVS338 - can't connect from outside

[MariaBellman]

We have some public ip-addresses. In the firewall, a Netgear FVS338, I have in the inbound services set up so one of the public ip-addresses will be routed to the Netgear SSL312 with its internal ip-address. It has been working fine for a couple of years meaning that my users can log in through the SSL312 and establish a vpn connection. Now I am going to change the SSL312 to a Netgear SRX5308. In that work I changed the ip-number for a short moment for the SSL312 and then back again in a try to have the new SRX5308 up in the air. When I have put ewerything back as before it is totally impossible to reach the SSL312 from outside, but no problems to reach it when I am inside in the LAN. The Netgear FVS338 in some way stops the traffic to the SSL312 from outside, or if it is the SSL312 itself, but when surfing with the public ip-address to it from inside it works and it is obvious that the FVS338 is a part of the possibility to connect. When I disable the service for routing in the FVS338 to the SSL312 its only possible to reach the SSL312 from inside with the internal ip whitch is understandable. But what is it that stops from accessing from outside? In parallell I have another service in the FVS338 with another public ip-address to MS Exchange that works perfect from the outside world.