I am unable to connect to a ReadyNAS Pro Pioneer today. It is my home office network. I have another ReadyNAS RN316 that is connecting fine. Last week I did upgrade the Wifi router to a Netgear R8000 if that's somehow related. Everything connects thru a Cisco SR2016T gigabit switch... same I've used for three years.
Do you have static IP on the NAS? It appears that your pioneer is not on your network range. You can direct connect your NAS to your PC and change the NAS IP or set it to DHCP.
From the image you have posted, the IP address of your ReadyNAS Pro Pioneer is not within the same network as with your RN316. I assume that your ReadyNAS Pro Pioneer has a static IP address. You may want to set your ReadyNAS Pro Pioneer as DHCP client.
An OS reinstall is one option, another is to do a direct connect (temporarily assign your PC a static address of 192.168.2.5, and directly connect the PC ethernet to the NAS. Then go to https:/192.168.2.4/admin again, and reset the address properly).
BTW, an OS reinstall will also reset your admin password back to the default ("netgear1"). Direct-Connect won't do that.
The best way is to use DHCP as Ixa suggests, and reserve the desired address in the R8000 router. That will also ensure that you get the correct DNS servers and subnet mask for your network.
