Tried the stand alone installer and now it works. :)

Downloaded the installer and installed that to a seperate folder, same problem.

But then I completely uninstalled it through Galaxy, installed it from the downloaded installer, and now it works.

It could be something to do with where GOG Galaxy installs the game, and the folder structure. Manually installing the game lets you choose where to put the game, maybe that's part of the issue.

The same for me. I have most of my game in a folder like "C:\games" etc. I guess that windows sometimes creates problems if you install games in something like "C:\Program Files (x86)".

By the way: Did the folderstructure changed? My savefiles seemed to be lost at first, but then I saw that my old saves where under "System Shock - Enhanced Edition\res\data" while the new ones are at "\System Shock - Enhanced Edition\res\missions\archive". Just in case anyone is looking for them.

Just noticed this as well, thought my save is gone at first.

I did that through GOG Galaxy alone, completely uninstalled, including saves and user files, reinstalled through Galaxy and got the same issue.

Had to uninstall, then install OUTSIDE of Galaxy using the downloadable installer for it to work. But now I can launch the game through Galaxy and it works

Yep can confirm that this did the trick.

Tried to install it manually. But now I get another error:
"The program can't start because D3DCOMPILER_47.dll is missing from your computer. Try reinstalling the program to fix this problem"

almost sure that means you are using win7, and need this:

Uninstall and reinstall in a "safe" place, ie NOT in Program Files (x86), do the trick for me...

On Windows 10 Pro as well... I get "ERROR!" after the initial cut scene finishes playing then it exits.

tried a new clean install outside program files as recommended?

also, starting to add the source port stuff to the FAQ.

It's definitely WHERE the game is located that makes it work or not work... I installed through Galaxy... after the cut scenes I got the "ERROR!"... went into the default Galaxy install location in Program Files (x86) and took the System Shock folder and manually moved it to the root of C, fired it up and I can now get to the main menu without the "ERROR!"... started a new game and all works well

This will definitely need a fix for Galaxy users who use the default install location

Wait, this thing requires KB2670838? Ok forget it then, not worth it.