---------------------------Microsoft Visual Studio---------------------------Windows Azure Tools for Microsoft Visual StudioThere was an error attaching the debugger to the IIS worker process for URL 'http://127.255.0.0:82/' for role instance 'deployment16(174).xxxxxxxxxxx_IN_0'. Unable to start debugging on the web server. See help for common configuration errors. Running the web page outside of the debugger may provide further information.Make sure the server is operating correctly. Verify there are no syntax errors in web.config by doing a Debug.Start Without Debugging. You may also want to refer to the ASP.NET and ATL Server debugging topic in the online documentation.
Nice! How confusing, the compute process didn't even startup but yet if I run it using the built in webserver all is fine. I knew it had to be related to DotNetOpenAuth as this was the only thing I had changed in my project since the last successful run.
So I started looking into the issue, now I knew it worked on the local dev server however I realised that it wasn't using IIS7 or IIS7.5 but the built in VS. This doesn't run anywhere near the same as IIS7.x which is what Azure is built upon. So I switched my MVC3 Web Application to use IISExpress, which is a lightweight version of IIS, and fired up the app.
I instantly got where the error message was:
HTTP Error 500.19 - Internal Server Error
The requested page cannot be accessed because the related configuration data for the page is invalid.
9: <sectionGroup name="dotNetOpenAuth" type="DotNetOpenAuth.Configuration.DotNetOpenAuthSection, DotNetOpenAuth">
7: <configSections> 8: <section name="uri" type="System.Configuration.UriSection, System, Version=126.96.36.199, Culture=neutral, PublicKeyToken=b77a5c561934e089" />
This section element wasn't needed, .Net 4 already includes System.Configuration.UriSection within the machine.config This is trying to load the v2 component, which is required for .Net 2 - .Net 3.5.
So where did it come from? Well the answer lies with NuGet, I had installed DotNetOpenAuth using Nuget
Install-Package DotNetOpenAuth -PreWhich along with the library references updated the web.config. The error here is not checking what .Net version the project is before it updates the web.config with the required sections.
As this is a prerelease version of DotNetOpenAuth my guess is it will be fixed before release, I'll be raising it as an issue any how.
Hope this helps.