Sorry Guys that I Found a problem after I downgraded my ETS back to the 1.17.1
After the download, I try to start the ETS but the Steam said that there is an error when downgrading because of the error in reading disk...
I tried renew the ETS version to 1.18 again, then I can still normally enter to the game.
I also tried to delete and reinstall the ETS, but the problem above still exists.
What should i do?
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Oh Finally I solved the problem. I uninstall the ETS first
Before reinstall, I select the 1.17.1 first.
Then It works