title: App_Offline.htm being created by Visual Studio 2017
body: <p>I'm using Visual Studio 2017 to run a web application project that was mostly developed with Visual Studio 2015. However, I never created the file "App_Offline.htm" file. No one on my team added it, either. It just randomly showed up while running Visual Studio 2017 and testing it out.</p>
  
  <p>Looking up the issue on here, I found <a href="https://stackoverflow.com/questions/4497257/this-application-is-currently-offline-to-enable-the-application-remove-the-app">This application is currently offline. To enable the application, remove the app_offline.htm file from the application root directory</a> where an answer stated:</p>
  
  <blockquote>
    <blockquote>
      <p>Just go to the root of your web directory, it should be there. it is something that VS puts there during certain tasks.</p>
    </blockquote>
  </blockquote>
  
  <p>This is unacceptable behaviour for testing a web application. This version of Visual Studio is unusable if Visual Studio "just decides" to make my web application offline. This answer/question is for an earlier version of Visual Studio, but if this feature used to be there then I assume that it must still be there because it seems to be the only way the file showed up.</p>
  
  <p>What specific tasks would make this file appear in the solution folder? How can I prevent it?</p>