I realise it\'s an early release and unstable. I wouldn\'t dream of swapping out the default webbrowser control for IE9 in any other project, but in this case I specifically
After a lot of Google-ing I have discovered that there are two different sets of keys for FEATURE_BROWSER_EMULATION for 32 bit and 64 bit applications. You need to set yours in the right place depending on the machine you are running. Also you need to make sure you install the correct version of the browser you want to emulate.
32 bit:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\MAIN\FeatureControl\**FEATURE_BROWSER_EMULATION**
Value Key: (DWORD) yourapplication.exe
64 bit:
HKEY_LOCAL_MACHINE\SOFTWARE\**Wow6432Node**\Microsoft\Internet Explorer\MAIN\FeatureControl\**FEATURE_BROWSER_EMULATION**
Value Key: (DWORD) yourapplication.exe
The value to set this key to is (taken from MSDN here) as decimal values:
9999 (0x270F) Internet Explorer 9. Webpages are displayed in IE9 Standards mode, regardless of the !DOCTYPE directive.
9000 (0x2328) Internet Explorer 9. Webpages containing standards-based !DOCTYPE directives are displayed in IE9 mode.
8888 (0x22B8) Webpages are displayed in IE8 Standards mode, regardless of the !DOCTYPE directive.
8000 (0x1F40) Webpages containing standards-based !DOCTYPE directives are displayed in IE8 mode.
7000 (0x1B58) Webpages containing standards-based !DOCTYPE directives are displayed in IE7 Standards mode.