Using Visual Studio 2013 in Windows 8.1, I\'ve been used to debug applications hosted in IIS by attaching to the w3wp.exe process running the Application Pool.
After
For some reason all w3wp.exe processes had stopped. I just recycled the app pool and refreshed the browser window and w3wp.exe started and showed up in the Attach to Process dialog as normal.
I don't know for sure if this is an IIS 10 related issue, but I never experienced this in earlier versions of IIS.