L-DR@GO

Sometimes its just network issues 
Troubleshooting your Network...
If you're still having the error. then try this solution 
 
 
1. Open Steam, go to LIBRARY -> GAMES
2. Right-click on Euro Truck Simulator 2 and open Properties
3. After the Properties window has opened click the LOCAL FILES tab and press BROWSE LOCAL FILES
4. A folder with game files opens. Remember the path to this Folder
 
Doesn't work?
1. Click Start -> Run (or WIN+R)
2. Type regedit and hit enter
3. Follow the path HKEY_LOCAL_MACHINE\SOFTWARE\TruckersMP
4. Look at the value parameter "InstallLocationETS2"
 
If they differ:
 
1. Copy the folder address from STEP 1
2. Change the value parameter "InstallLocationETS2" (Insert the copied folder address)
3. Click OK.
 
Note: you have to manually copy the path to TMP client it looks okay when you check it but it can be the issue coursing the Error!. 
 
After that, many users get another error: "Connection error - retry?" In this case, open Task Manager, close all Programmes of TruckersMP/ETS, and try to start the Launcher as an administrator again.