I cannot found Web Site Administration Tool in visual studio 2015. where is it?
It used to be on menu \"website > Administration Tool\" or \"Project > Administration
You need to use the port that you have configured in your app,
My command:
iisexpress.exe /path:C:\Windows\Microsoft.NET\Framework\v4.0.30319\ASP.NETWebAdminFiles /vpath:"/ASP.NETWebAdminFiles" /port:58835 /clr:4.0
Also there's a video search for "How to access ASP .Net Web Site Configuration Tool using Visual Studio"