Ok I solved both problems.   The connection issue was solved by changing on the client the profiles for the firewall rule (created during the original installation of Networker on Windows Server 2008 R2) of nsrexec from Public to Private (Private + Public).   For completeness I'll report here the solution already found for the Configuration window not appearing on screen: - in the ribbon under "Window" select "Tile vertically" or "Tile horizontally" and out of nowhere will appear the Configuration Window.   Thanks bingo for your help.Sadly I have no voice in the update matter 
Hi, I have inherited an up and running library managed with Networker 7.6.3.3. I have zero experience with Netwworker so please bear with me.   I have a problem with the Administration GUI Configuration icon not showing any related window (the one with the Groups, Clients, Directives etc.). I have also a problem with a client not reachable by the server but from its side it can reach the server instead.     About the GUI problem. In the Administration GUI there are four major buttons for: - Monitoring - Configuration - Devices - Media While using these buttons I got a non usual behaviour. When pressing Monitoring, Devices and Media it highlights the related window but if the previous window I was using is maximized in the GUI then the requested window will stay hidden under it no matter what. If a window of Monitoring / Devices / Media is minimized and I click on its relative icon to highlight it it will stay minimized. I have to manually click on hit to expand it. When I see online video of this old version of NMC I see the usual behaviour which when you pressed one of these four icon the related window is highlighted. What can I do to change this behaviour?     About the connection problem to the client . I want to see the contents in the configuration window in order to try finding what's causing the connection problem with the client. This client cannot be reached by the server nor while trying to do a backup nor through command line with: "nsradmin -p nsrexec -s ".   This client has a running nsrexecd and instead it can reach the server through command line with: "nsradmin -p nsrexec -s ".   The host files, on the client and the server, do contain both entries (client and server). The client and the server can ping each other. The nslookup resolves their respective IP addresses. The server file on the client contains the in it.  The and are the same found throgh command line with:  "nsradmin -p nsrexec -s "   I suspect that the problem is on an OS level but I can't find it.   Thanks  
EMC NetWorker 7.6.3 : NMC Administration GUI Configuration icon not showing 
anything / Client connection problem