I am using Selenium web drivers, and today, for no apparant reason I started getting an error with the message\"Chrome Automation Extension has crashed. Click this balloon
In my case I have to run it under Admin, I fixed it by updating .NET framework. You can update this in Windows Update. I updated every item that is related to .NET framework, including crucial ones and optional ones.
Here are two items I updated:
2018-01 Preview of Quality Rollup for .NET framework (KB4057272)
.NET framework 4.7.1 (KB4033369)
Hope this helps
Edit: I run Win 10 with chromedriver 2.34 and Chrome v64.0.3282.140(64-bit)