Transcribed from a phone call

I cannot browse my concentrator any more. I've put it on the center's LAN, and they assure me there is DHCP and internet access, but I can't browse my concentrator any more. Please help

The best is to plug out the ethernet cable from your concentrator and plug the same cable into your Laptop computer, configured to get an automatic IP, and check whether you can access the internet.

The specific IP you need to reach is www.pnpscada.net (196.22.139.148) and the specific port that you need to be able to connect to is TCP 1194, for OpenVPN connectivity.

So, for instance, you should be able to go to a command prompt and go:
telnet 196.22.139.148 1194
...and it should connect you. If you cannot make a connection to that port, your concentrator is also not going to be able to do it. Complain at their IT guys until your computer can get connectivity, and once that works, plug it out and plug in the concentrator again and see if you can browse your concentrator (after 5 or 10 minutes).