These are the mod's folders, depending on your game's version:
For Entrenchment with no patch: "Mods-Entrenchment v1.01"
For Entrenchment with patch 1.02: "Mods-Entrenchment v1.02"
For Non-entrenchment with patch 1.15: "Mods-v1.15"
For Non-entrenchment with patch 1.16: "Mods-v1.16"
For Non-entrenchment with no patch: "Mods"
Make sure that your mod is in the proper mod's folder, and in this folder there is a folder with the mod's name, and in it there are the gameinfo, particle, pipelineeffect, string, textures, etc. folders