SOLVE
Delefe file C:\ProgramData\TruckersMP\core_ets2mp.dll
To fix this problem you must delete file name: core_ets2mp.dll in folder: C:\ProgramData\TruckersMP. After that open multiplayer and problem solved.
How to Show Hidden Files and Folders in Windows 10
To show the files and folders automatically hidden in your Windows 10 computer, you can use one of the two methods introduced in this text.
Video guide on how to show hidden files and folders in Windows 10:
Step 1: Open Folder Options.
Open This PC, click View and select Options.
Step 2: Show the hidden files and folders in the View settings.
In the Folder Options window, choose View, select Show hidden files, folders, and drives, and then click OK.
Now, go ahead to put them into practice, and you can show the hidden files and folders on your PC.