@captainwalker This indicates that the download of the file was broken at a very early stage and thus incomplete.
The above describes the manual install.
I will list the steps for you (though you did all of this, it’s just an incomplete download):
Go to
https://triplea-game.org/download/
Klick on the red “Download for Windows (64-bit)” field.
Windows opens a window where you are asked to save the file.
In this window confirm by clicking “Save”.
Once your browser confirmed the complete download go to the place you saved the file in. This should look similar to this:
085350bf-7d50-4304-b6c4-fba992f52591-image.png
Now doubleclick the file and follow Windows’ installation procedure.
You see how different the complete download looks compared to what you got.