WlanSetProfileEapXmlUserData function (wlanapi.h)

The WlanSetProfileEapXmlUserData function sets the Extensible Authentication Protocol (EAP) user credentials as specified by an XML string. The user credentials apply to a profile on an adapter. These credentials can be used only by the caller.


DWORD WlanSetProfileEapXmlUserData(
  [in] HANDLE     hClientHandle,
  [in] const GUID *pInterfaceGuid,
  [in] LPCWSTR    strProfileName,
  [in] DWORD      dwFlags,
  [in] LPCWSTR    strEapXmlUserData,
       PVOID      pReserved


[in] hClientHandle

The client's session handle, obtained by a previous call to the WlanOpenHandle function.

[in] pInterfaceGuid

The GUID of the interface.

[in] strProfileName

The name of the profile associated with the EAP user data. Profile names are case-sensitive. This string must be NULL-terminated.

Windows XP with SP3 and Wireless LAN API for Windows XP with SP2:  The supplied name must match the profile name derived automatically from the SSID of the network. For an infrastructure network profile, the SSID must be supplied for the profile name. For an ad hoc network profile, the supplied name must be the SSID of the ad hoc network followed by -adhoc.

[in] dwFlags

A set of flags that modify the behavior of the function.

On Wireless LAN API for Windows XP with SP2, Windows XP with SP3,Windows Vista, and Windows Server 2008, this parameter is reserved and should be set to zero.

On Windows 7, Windows Server 2008 R2, and later, this parameter can be one of the following values.

Value Meaning
Set EAP host data for all users of this profile.

[in] strEapXmlUserData

A pointer to XML data used to set the user credentials.

The XML data must be based on the EAPHost User Credentials schema. To view sample user credential XML data, see EAPHost User Properties.


Reserved for future use. Must be set to NULL.

Return value

If the function succeeds, the return value is ERROR_SUCCESS.

If the function fails, the return value may be one of the following return codes.

Return code Description
Access is denied. This value is returned if the caller does not have write access to the profile.
The network connection profile is corrupted. This error is returned if the profile specified in the strProfileName parameter could not be parsed.
A parameter is incorrect. This value is returned if any of the following conditions occur:
  • hClientHandle is NULL.
  • pInterfaceGuid is NULL.
  • strProfileName is NULL.
  • strEapXmlUserData is NULL.
  • pReserved is not NULL.
A handle is invalid. This error is returned if the handle hClientHandle was not found in the handle table.
Not enough storage is available to process this command.
The request is not supported.

This value is returned when profile settings do not permit storage of user data. This can occur when single signon (SSO) is enabled.

On Windows 7, Windows Server 2008 R2 , and later, this value is returned if the WlanSetProfileEapXmlUserData function was called on a profile that uses a method other than 802.1X for authentication.

The service has not been started. This value is returned if the Wireless LAN service is not running.
Various error codes.


The WlanSetProfileEapXmlUserData function sets the EAP user credentials to use on a profile. This function can be called only on a profile that uses 802.1X for authentication. On Windows Vista and Windows Server 2008, these credentials can only be used by the caller.

The eapType parameter is an EAP_METHOD_TYPE structure that contains type, identification, and author information about an EAP method. The eapType member of the EAP_METHOD_TYPE structure is an EAP_TYPE structure that contains the type and vendor identification information for an EAP method.

For more information on the allocation of EAP method types, see section 6.2 of RFC 3748 published by the IETF.

On Windows 10, Windows Server 2016, and later, the WlanSetProfileEapXmlUserData function is enhanced. EAP user credentials can be set for all users of a profile if the dwFlags parameter contains WLAN_SET_EAPHOST_DATA_ALL_USERS.

All wireless LAN functions require an interface GUID for the wireless interface when performing profile operations. When a wireless interface is removed, its state is cleared from Wireless LAN Service (WLANSVC) and no profile operations are possible.

The WlanSetProfileEapXmlUserData function can fail with ERROR_INVALID_PARAMETER if the wireless interface specified in the pInterfaceGuid parameter has been removed from the system (a USB wireless adapter that has been removed, for example).

The WlanSetProfileEapXmlUserData might cause wireless connection failure when you use EAP-TTLS and the API is called from a 32-bit application running on a 64-bit operating system (OS). Your application should be built for the same CPU architecture as the target OS.

Windows XP with SP3 and Wireless LAN API for Windows XP with SP2: This function can only be used for Protected EAP (PEAP) credentials. It can't be used for other EAP types.


Minimum supported client Windows Vista, Windows XP with SP3 [desktop apps only]
Minimum supported server Windows Server 2008 [desktop apps only]
Target Platform Windows
Header wlanapi.h (include Wlanapi.h)
Library Wlanapi.lib
DLL Wlanapi.dll
Redistributable Wireless LAN API for Windows XP with SP2

See also