Hi @aleksw
You are using an external host, the host name will be redirected to your local IIS, so you need to run Visual Studio with administrator rights, so please check if you are running VS with administrator rights.
If you still can’t solve the problem, you can refer to the link below for troubleshooting: Error: Unable to Start Debugging on the Web Server.
There is also a link about the specific operation process of the entire configuration. You can check the document to see if there are any differences or omissions in some configurations.
Remote Debug ASP.NET on a Remote IIS Computer.
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