new mods no longer appear on game if not downloaded from the game's repository

about a week ago I've started to notice that any mod I download does not appear in the game unless i download it from the repository inside the game. I've always just moved new mods into a mod folder manually but now that doesn't work. any suggestions as to why this is happening?

 

this is happening to me too. I "deleted" the mods\vehicles folder and open the game and working again (I test in garage mode, if the option to select the car does not show up it means it's broken). Then I move a mod one by one. it works until like I have 5 and then If I move all together it does not work again. It was working very nice before. I downloaded 3 mods and then this started to happen. (of course I tested without these last 3)
I made a new user already, uninstalled the game and the result is the same.

edit: finally i found out only one mod ruined all 78 mods active. I suggest you start with the last ones and move to the game one by one until the game does not show any mods. good luck