Just got the definitive edition of Endless Space 2 and installed it.
When I try to run the game, I see the icon of the game in the task bar for several seconds, the loading icon and then nothing. The game exits (before even starts) and that's it.
No error message, nothing.
Any suggestions.
System is up to date with everything.
Windows 11
GPU RTX 4090
CPU 13700K

I think I found the problem, I had to run it as administrator, which is extremely dumb, as a game should not require such privileges to run. I don't remember any other game requiring this. Any ideas how to not run it as administrator would be appreciated.

Is it installed to a Windows file like c:\Program Files?

No, it's installed in a custom directory, actually the one where I install all games (including those from GOG).

If you cannot start the game, you should try the following:

* Deactivate Onedrive (if you use it)
Or
* Start the game as admin

Hi,
I had the same problem today.
After a fresh installation, the game would not start. :-(
The game icon appeared briefly in the taskbar and then disappeared again without an error message.
Fortunately, I found a log file ("output_log.txt") of the startup under "...\Endless Space 2\EndlessSpace2_Data" and the note there:
'...
(Filename: C:/buildslave/unity/build/artifacts/generated/common/runtime/DebugBindings.gen.cpp Line: 51)
Current enviroment variable 'OPENSSL_ia32cap' value is ':~0x20000000' for target 'Machine'
(Filename: C:/buildslave/unity/build/artifacts/generated/common/runtime/DebugBindings.gen.cpp Line: 51)
Trying to set the enviroment variable 'OPENSSL_ia32cap' to ':~0x20000000' for target 'Machine'
...'
After setting this system variable with the specified value:
temporarily:
set OPENSSL_ia32cap=:~0x20000000
or
globally:
setx OPENSSL_ia32cap ":~0x20000000"
the game is now running as a normal user. :-)