Important  The Native 802.11 Wireless LAN interface is deprecated in Windows 10 and later. Please use the WLAN Device Driver Interface (WDI) instead. For more information about WDI, see WLAN Universal Windows driver model.
The IHV Extensions DLL calls the Dot11ExtSetProfileCustomUserData function to save data within the system registry that is specific to the current user and network profile used for the basic service set (BSS) network connection.



DWORD Dot11extSetProfileCustomUserData(
  HANDLE hDot11SvcHandle,
  HANDLE hConnectSession,
  DWORD dwSessionID,
  DWORD dwDataSize,
  LPVOID pvData



The handle used by the operating system to reference the wireless LAN (WLAN) adapter. This handle value was specified through a previous call to the Dot11ExtIhvInitAdapter IHV Handler function.


The handle used by the operating system to reference the connection session with the BSS network. This handle value was specified through a previous call to the Dot11ExtIhvPerformPreAssociate IHV Handler function.


The session identifier (session ID) of the current user.


The size, in bytes, of the buffer referenced by pvData .


A pointer to a caller-allocated buffer, which contains the data in a format defined by the IHV.

Return Value

If the call succeeds, the function returns ERROR_SUCCESS. Otherwise, it returns an error code defined in Winerror.h.


The operating system will not encrypt the data referenced by the pvData parameter before storing it within the system registry. The IHV Extensions DLL should use its own encryption algorithm to encrypt the data prior to calling Dot11ExtSetProfileCustomUserData.

For every wireless WLAN profile used by the Native Wifi AutoConfig service, Windows maintains the concept of custom user data. This custom user data is initially non-existent, but can be set by calling the Dot11ExtSetProfileCustomUserData function. The custom user data gets reset to empty any time the profile is modified by calling the Dot11ExtSetCurrentProfile function.

After custom user data has been set, this data can be accessed using the Dot11ExtGetProfileCustomUserData function. The operating system stores the data under the system registry HKEY_CURRENT_USER key for the user that is referenced by the handle passed in the dwSessionID parameter.


Minimum supported client Available in Windows Vista and later versions of the Windows operating systems.
Target Platform Desktop
Header wlanihv.h (include Wlanihv.h)

See Also



Dot11ExtIhvPerformPreAssociate Dot11ExtGetProfileCustomUserData