It Happened - Malware encrypted all source codes

Below is the narrative how one of my friend suffered for no apparent fault of his.
All personal information are changed as per Privacy rules.

All text below are of my friend and all credits goes to him as he bounced back strong within two months time, re-creating all lost project files.

What happened?

A company located in <country> contacted us wanting to work with us, after going back and forth, we agreed to sign a contract with them regarding developing projects for them exclusively.

We signed the contract and we starting working with them, the first project they requested is to finish developing an existing project they had, they sent us the source codes of this project, also they sent us demos (EXE) and Documents (Word Documents).

We as a company, always set assignments to each employee within the required department depending on the project requirements, in this case, the first department was the research and marketing team, the first task was to read the documents, review the demos to be able to fully understand the concept of the requested project.

Once the team ran the EXE demos, their devices were infected by a virus under the name (makop) which is an encryption virus under the WannaCry virus family, After doing some research about this virus we found out later that this virus is a network (online) virus which means it infects every device that is connected to the same network.

Unbeknownst to us, within minutes the department PCs were encrypted and within less than 48 the the whole company was infected and all of our files were encrypted, personal PC, Work PC, Laptops, servers, NAS server, and 4 of our online servers.

We did scan the files as we always do, but Kaspersky didn't detect the any virus which is what made us trust the files, mistakes happen.
It all happened within minutes, and (Makop) virus leaves back doors, meaning while we were trying to recover and take backups, the virus was running in the background for 48 hours and encrypting everything.
Also one of the main cause was this virus (Makop) is undetectable, because it's a new virus that falls under the WannaCry virus family.

Scammers, hackers, thieves, out laws, etc... are always finding a new way of destroying people's lives, no matter how much a person can be careful there will always be someone out there inventing a new way to ruin this person life.

But in the end we get up and move on, as the German philosopher "Friedrich Nietzsche" once said, "What doesn't kill you, makes you stronger".