A) Check to make sure that IISExpress is running. First, start your project in Visual Studio, then click the Start button and search for ‘Resource Monitor’. Expand the ‘Network’ section and look for IISExpress. You could also use Ctrl-Alt-Delete and choose Task Manager to see whether IISExpress is running. If it’s not there then there is a problem with IISExpress and it’s not even running. In this case you can work around the issue by configuring the web project to run in IIS.
- Make sure IIS is set up on the machine
How to enable IIS on Windows
- Configure Visual Studio to use IIS to run the web project
Use Local IIS as a Web Server in Visual Studio
B) Check the version compatability of IISExpress with Visual Studio. IISExpress 10 does not work with VS 2017, for instance.
C) There are any number of reasons why IISExpress night not be starting
IISExpress Troubleshooting on Stackoverflow