FaultInIEFeature function

This synchronous function is invoked by the client of a Windows Internet Explorer feature before the client accesses the feature.


HRESULT FaultInIEFeature(
  _In_    HWND         hWnd,
  _In_    uCLSSPEC     *pClassSpec,
  _Inout_ QUERYCONTEXT *pQuery,
  _In_    DWORD        dwFlags


hWnd [in]

A handle to the parent window of the HTML dialog box.

pClassSpec [in]

A pointer to a union that provides ways of mapping to a CLSID. Note that uCLSSPEC is defined in sdk\inc\wtypes.h.

pQuery [in, out]

A ointer to a structure that contains a list of attributes used to look up a class implementation. The installed version number is returned in FIEF_FLAG_PEEK, which is passed in.

dwFlags [in]

The control behavior. The following values are valid.


Force JIT, even if the user has canceled a previous JIT in the same session, or has specified to Never JIT this feature. Note: For Internet Explorer 7, this flag is not respected; it is overridden by E_ACCESSDENIED.


Do not faultin, just peek. Note: Peek also returns the currently installed version in the QUERYCONTEXT. For Internet Explorer 7, it disables the Java dialog box.


Ignores local version as being satisfactory and forces JIT download. Typically, this is called by code download, or by another caller after a CoCreateInstance call has failed with REGDB_E_CLASSNOTREG or ERROR_MOD_NOT_FOUND (missing a dependency DLL). Note: The registry might show that this feature is installed when it is not, or when it is damaged. For Internet Explorer 7, this flag is not respected; it is overridden by E_ACCESSDENIED.

Return value

Returns one of the following values.

Return codeDescription

Behavior is installed. Call CoCreateInstance or IMoniker::BindToObject or another system service to invoke the class or MIME handler.


The class or MIME handler is not part of an Internet Explorer feature. Call CoCreateInstance, IMoniker::BindToObject, or some other system service to invoke the class or MIME handler. Active setup settings are not found in registry.


The administrator has turned off the JIT feature.



If the feature is already installed, then the function succeeds and the client should attempt to access the feature. Successful return does not guarantee that the feature is fully installed, or that the feature will work. The client should still provide access to the feature with proper error checking.

Note  The importance of this function degraded significantly after Microsoft Internet Explorer 6 SP1b and Windows XP, due to a lack of dependence on JIT in components.


Minimum supported client

Windows XP

Minimum supported server

Windows 2000 Server


Internet Explorer 4.0