I have a clean installed windows 10, and a clean installed VS 2015 Update 1 with RC1 ASP.NET Tools. When I start a new ASP.NET MVC project without any authentication!, and H
I think my problem was because I had the "Enable SSL" option checked but the certificate was not installed on this machine.
So, running the site with Ctl+F5 installed the certificate and then I was able to debug the site solving my issue.
For me, on my clean installation, not having the URL Rewrite extension installed was causing this error.
http://www.iis.net/downloads/microsoft/url-rewrite
After installation, I no longer get the error.
The authentication answers above didn't make any difference in my case.
I got this error when I was trying to debug an ASP.NET Core (RC1) project with the Enable SSL
option checked. Previously I had moved the IIS Express Development Certificate
into the Local Machine\Trusted Root Certificates
folder in Certificate Manager in an attempt to prevent Chrome showing SSL errors. It turns out that that certificate is needed in the Local Machine\Personal
folder. Copying the certificate there solved the problem.
Finally I found the solution. As I told I don't use any authentication in this project, so I switched off "Enable Anonymus Authentication" and "Enable Windows Authentication". But it seems, we mustn't switch off "Enable Anonymus Authentication", because of we will get that "An error occurred attempting to determine the process id of the DNX process hosting your application" error.
So the solution is to keep switched on "Enable Anonymus Authentication" even if you don't use any authentication.
The poster has stated that they found the answer to their question but I experienced the same error message with RC1 and the accepted answer did not resolve my issue. I see that Sven Gillis is still hunting for a solution as well so I'd like to share what solved the issue for me.
Turns out that the error can be triggered by a bug in RC1 Update 1 (and all prior versions) which occurs if the installation is being used via a windows login name that has a space in it. e.g. "Tim Smith".
I was not able to find a patch but there is a work around. Just create another user account on the machine that doesn't have a space in it (e.g. "Tim") and to use visual studio under that account. In my case this solved the issue. I can now create web projects in Visual Studio 2015 Community Edition Update 1 via the Asp.Net 5 templates and can run them via F5 and Ctl+F5 from within visual studio and I no longer receive the error.
However if I switch to the original user account on the machine that has a space in it, I still receive the error when trying to run a project generated from the same template. Same code ran from two different windows user accounts producing two very different results. I hope this helps someone else, I wasted 7 full days hunting for the solution to this issue.