I have copyed the .yaml -Files into the mods-folder (E:\Documents\Master of Orion\Mods), but the game didn't find any mods. When i click on Mods-Button and acept modding eula, i get the message "You don't have any mods in your Mod folder"
Where is the mistake?

Try to look into:
c:\Users\"UsersName"\Documents\Master of Orion\Mods\

Edit:
It should work on Win10

c:\Users\"UsersName"\Documents\Master of Orion\Mods\ doesn't work on my system (win 7)

BTW the documents folder on c:\Users\"UsersName"\Documents is empty because on system installation i ve moved my documents to drive E:\ my default documents folder is on E:\Documents\. Since 7 years without any problems.

The save games are located in E:\Documents\Master of Orion\Saves\. There is an Mods folder too, but it doesn't work to copy any .yaml file into it.

But... thanks for picture.
Every mod must habe his own folder. Thats my failure, i ve copyed the rare .yaml file into the mod folder.

Thank You, now it works.