http://localhost:3980/ is not a valid Win32 application RRS feed

  • Question

  • User513960417 posted

    When creating a new ASP.NET MVC Web Application, after the project builds I try to run/debug it with F5 and I get this error:

    Unable to start program 'http://localhost:3980/'.

    http://localhost:3980/ is not a valid Win32 application.

    I have tried going into tools>>options>>Projects and Solutions>>Web Projects>> Checking 'Use the 64 bit version of IIS Express for web sites and projects'

    I have also tried going into the IIS express>>config>>schema and editing IIS_schema.xml so that "enable32BitAppOnWin64" is set to "true"

    My version of Visual Studio is Visual Studio 2015 Enterprise (I also got the same error with VS 2015 Enterprise Update 2)

    My version of IIS Express is 10.0

    My OS is Windows 7 Service Pack 1

    I am using ASP.NET 4.5.2 and trying to run a File>>New Project>>ASP.NET Web Application >> MVC

    Tuesday, June 21, 2016 12:50 PM


  • User513960417 posted

    This issue was caused by Visual Studio running the app on IE11 64-bit. When I switch the browser to IE11 32-bit or Firefox (also 32-bit), the app runs fine on localhost in the browser.

    • Marked as answer by Anonymous Thursday, October 7, 2021 12:00 AM
    Tuesday, June 21, 2016 2:52 PM