In case you encounter this notice in your connection log (right click OpenVPN icon => "View Log") and get disconnected by this, then there is a simple step to resolve this.

When you get this error, you generally have problems with our/your DNS hostname. Do this (ONLY if you are having this problem!):

Open your "username.ovpn" (usually at C:\Program Files\OpenVPN, Program Files (x86) on 64bit machines) file with a text editor and check for the line: 

"remote uXXXXXX.nvpn.so 1194"

substitute this line with your actual assigned IP (shown in Members Area, in this example 178.221.57.110)

"remote 178.221.57.110 1194"

Important note: Using a fixed IP in the config file is not recommended and means you would have to repeat this step on every Country/IP change again, so only do it if needed.