I’ve just added another project to Unity HUB and when I try to open a script Unity doesn’t launch Visual Studio, it doesn’t do anything. I looked into preferences and it is configurated to open the scripts with visual studio. I open another project, which I already had and it works correctly, when I try to open a script in that project, Unity launches correctly Visual Studio so I don´t know what is happening.
Try hitting the menu Assets → Open C# project
If that fails, delete the .csproj and .sln and other visual studio crud in the root of your project and try the above again. Unity is supposed to recreate those on demand and if they get borked in some way, this can happen.
I will try that, thank you very much