Try deleting the hidden folder .vs in the solutions directory. You cannot have the solution open when doing that.
How do I get Visual Studio 2019 to connect to IIS Express?
Using the latest version of Visual Studio 2019 and opening the ASP .NET Core Web Application template, I try to run the default code without any changes, but I continually get and error message saying, "unable to connect to web server IIS Express". I tried everything from deleting the .vs folder, changing the application port number, restarting my computer, and uninstalling then reinstalling visual studio. I trying it again on another laptop and it worked flawlessly. I don't know what is special about my PC, but I need help. Both computers used Windows 10. My PC used Windows 10 pro and my laptop used Windows 10 home. attached is a screen shot of what I'm seeing.