Installation loses network card in step 3/3 Net Config

Hello

I’ve been using Virtualmin on different servers for quite some while but I still think I’m a newbie so…

Now I’m trying to install a new server. I’ve tried Debian 9.5, Debian 9.4 and Debian 8.11 but nothing seems to work…
Here’s the full problem…

During install I keep a terminal window open from my pc that keeps pinging the server’s public IP
When the install reaches Step 3/3 - Net Config than the connection is lost. Pinging stops replying.

At the end of the setup the install script tells me it can’t determin what the network interface is that I want to use. When I exit the install script and do an ifconfig I can’t see my network interface anymore but it was there before I started and it kept on working until that step.

I really hope I’m not the only guy that is having this problem but I can’t find someone else online or in the forums so I’ve posted this…

Hope anyone can help…

PS: Maybe one more important thingy…

I’ve set my IP address, gateway and DNS server manually during the install of the Debian OS. I don’t know if this is important but thought I should mention it.

Greetings