title: Web Installer for an ASP.NET application failing on machines running IIS7
body: <p>I have a relatively simple ASP.NET application that I am trying to create an installer for. I am currently using Visual Studio 2008's "Web Setup Project" which, though I'm told is not ideal, has proved no problems when installing on Windows Server 2003 &amp; IIS6.</p>
  
  <p>IIS7 on Server 2008 and Vista has proved substantially more difficult. The installer starts off fine before halting with an unhelpful "<em>The installer was interrupted before  could be installed. You need to restart the installer to try again.</em>"  UAC is switched off, and I've already ensured I'm executing the installer with administritive privledges.</p>
  
  <p>The problem sounds identical to the issue outlined in <a href="http://www.nitiative.com/portal/Home/tabid/36/EntryId/15/IIS7-Web-Setup-Install-Error-Status-1603.aspx" rel="nofollow noreferrer">this blog post</a>, however I have the IIS6 Metabase Compatibility role service installed already. I've also tried playing around with AppPools, the Integrated/Classic pipelines and so on, all to no avail.</p>
  
  <p>I've since turned on MSI logging and, whilst I found nothing concrete, I believe the rollback begins somewhere around this error message.</p>
  
  <blockquote>
    <p>The error indicates that IIS is in 64 bit mode, while this application is a 32 bit application and thus not compatible.</p>
  </blockquote>
  
  <p>This doesn't make any sense to me whatsoever, as both Vista and Server 2008 are 32-bit installations. I suspect it's a red herring, but I can't be sure.</p>
  
  <p>Has anyone encountered a similar problem, and if so, is there a solution that doesn't involve me moving to a different installation framework?</p>