Over the past couple of weeks I have been trying to use the Visual Studio 2010 Performance Analyizer on a web site but kept on getting;
VSP 7008: ASP.net exception: “The web site could not be configured correctly; getting ASP.NET process information failed. Requesting ‘http://localhost/VSEnterpriseHelper.axd’ returned an error: The remote server returned an error: (404)
The site is a relatively complex IIS6 site with a number of smoke and mirror redirects so I guessed this complexity was confusing the tools. I contacted Microsoft Support to help. During a shared-desktop session with support it started working! Ah the curse of the support person making it work just by looking at it. What actually happened is that when I launched the Performance Wizard I incorrectly gave it a file URL (\\localhost) rather than a web URL. The wizard prompted to say there were no DLLs to profile but I said to continue (not realising my mistake). The profile finished with no results. I corrected the problem (//localhost) by editing the resulting profile NOT by creating via a new wizard. It works?! So I had created a workaround 
. I then manually added the missing target DLLs and re-ran the profile. No problems, everything worked.
There you go, if you are running IIS6 and having problems getting the Profiler to connect, why not try this ridiculous workaround.
IT Bytes 
You can also generate a sample profile report for the visible time range to understand where most of the work was spent. If you click on the Execution label in the active legend, the report will show up in the Profile Report tab.