Createdefaultbuilder does not exist. CreateDefaultBuilder uses is no longer recommended going forward, and the programming model is no longer used in ASP. cs. That's why I submitted this as a bug because it shouldn't happen. Nov 30, 2021 ยท The problem is your application name is WebApplication, so the IDE thinks it's referring to the namespace instead of the build in WebApplication class. net core web ASP. ConfigureWebHostDefaults extends IHostBuilder to add web-specific configurations (Kestrel, URLs, etc. json & appsettings. While both serve the same core purpose—bootstrapping your application—they differ significantly in design, features, and use cases. Even you can also the other overloaded version of the CreateDefaultBuilder method which does not take any parameter. Host' (are you missing an assembly reference?) Initializes a new instance of the HostBuilder class with pre-configured defaults. zwwkrz udrqc jiwl yqnwt yox yolzszn qsuxyixs yhck hbwav nhz