EDITED 2 days later:
After messaging with GOG support, it turned out that the VC++ install was indeed included in the offline installer. Furthermore I noticed that UE4PrereqSetup_x64.exe checks for its presence and installs it if absent. For whatever still unknown reason, it didn't do that for me, despite re-running the offline setup. To make it work in the end I had to uninstall the UE4 prerequisites by running UE4PrereqSetup_x64.exe again, found in the game's folder, and uninstall VC++ 2015 x64 as well. After doing this a reinstallation worked. I can confirm that the installation using any offline installer on a freshly installed Windows, set-up for testing, succeeded without errors. Maybe this is still helpful to anyone. (This is almost the same message I posted in the
release thread, because I'm that lazy.)
I've installed the game using the offline installer. When I tried to load the first level, I got an error popup saying
FATAL ERROR and loading just stalled. Repairing the game using
GOG Galaxy solved the problem.
I've verified that the offline installer doesn't install
Microsoft Visual C++ 2015 Redistributable (x64) - 14.0.24215, which apparently, according to
Epic Games, is required to install UE4 prerequisites successfully.
Alternatively you can install this by yourself:
1. Download Microsoft Visual C++ 2015 Redistributable (x64) - 14.0.24215 and run it:
https://www.microsoft.com/en-US/download/details.aspx?id=53840 2. Run the UE4 prerequisites installer that can be found on your drive:
%GOG GAMES PATH%\Phantom Doctrine\Engine\Extras\Redist\en-us\UE4PrereqSetup_x64.exe I'll drop a message to GOG support, informing them about the currently missing redistributable package for the offline installer.
Midoryu
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“Believe those who are seeking the truth. Doubt those who find it.” André Gide(1869-1951), French author Edited 3 minutes later: Added missing word ("that").