In My Case I was unable to dubug application I also get same error Unable to debug Application , Unable to connect to remote server . The Issue occurs when APi does'nt match with IIS when creating virtual directory it will just create a path but it will never match if you deleleted some how ... Solution :

Step 1 : Open IIS service manager Start Defaulat website by right clickon on icon and click on start enter image description here else if its already running then right click on sites and click on Add Website enter image description here a) Add path of webapi and fill the fields