If you search for this topic today, you’ll find a post from 2006 on the “Scripting Guy” blog that contains some information on how to query the registry key to figure out the default scripting host. Great!

Except it’s wrong

To be fair to Scripting Guy, he was correct when he wrote that article, but the change in this behaviour is one of the lesser known exciting features of Windows Vista.

So, how does it work now?

Through the magic of procmon, we can figure out what changes are taking place when we change the script host

Et voilà!

Here’s a PowerShell snippet for querying this value

1(Get-ItemProperty registry::HKEY_CLASSES_ROOT\VBSFile\Shell).'(Default)'

Open means WScript, Open2 means CScript.