First things first, I'm a complete novice with all of this so please excuse my inexperience.
I followed instructions for installing and configuring Ubuntu 16.04, OwnCloud 9 and Apache on my N54L server. I've also set up SSL. Everything works fine when I access the cloud on my Android app, i.e. I can download/upload files. However, I then installed an OpenVPN service on my Ubuntu server (OpenVPN through my hired seedbox from FeralHosting) as I wanted to encrypt all of my traffic. Obviously this has given my server a different external IP address. When I try to create a new account in the OwnCloud Android app using the VPN's external IP address on my Ubuntu server, I get 'Malformed server configuration'.
I'd really like to keep my VPN going so I was wondering if there's something that I need to configure, or is it an issue with me using a seedbox provider as the VPN source? Perhaps I should use a standard VPN service?
Any help, preferably in layman's terms if possible, would be greatly appreciated.