@Christian-Ehrlicher said in Qt Creator: cmake errors after downgrade of MSVC compiler: 17.9 should also work. Make sure to start with a clean build dir and also no CMakeLists.txt.user in the source tree I did everything, but forgot about .txt.user Will try that... EDIT: However, after the torturous downgrade/upgrade experience, my VS debugger decided to behave, so I'll keep you advice for the future.

@damedameu It is a very bad idea to work as root, just like it is a bad idea to work as administrator on Windows. As root you have full access to the system, so it is easy to break something. Also, you make the life of hackers easier this way.