Those unfortunate souls battling with this one and wondering how this dude could b so cruel as to say "Fixed it!" without telling us how... try this:
Microsoft documents the solution this way...
1. Open a command prompt and navigate to the %systemdrive%\Inetpub\AdminScripts directory.
2. Type the following command:
cscript.exe adsutil.vbs set W3SVC/AppPools/Enable32BitAppOnWin64 “true”
3. Press ENTER.
taken from:
http://www.microsoft.com/technet/pro....mspx?mfr=true
But, after this & all the forum suggestions i tried, i went into IIS Manager, opened the Application Pools link, and noticed that my DefaultAppPool was stopped by one or the other process i tried. So, in my case, i switched 32bit support off again (the above command but with a 0 at the end) and started the DefaultAppPool up again. All is well now. It's not giving me that ridiculous "Cannot find..." nonsense.
Lemme know how it goes & if any1 had the same issue...
Martin