wndparams (PWNDPARAMS)
For a value set, the valid values for the fsStatus field are WPM_CBCTLDATA and WPM_CTLDATA.
The flags in the fsStatus field are cleared as each item is processed. If the call is successful, the fsStatus field is NULL. If any item has not been processed, the flag for that item is still set.
ulReserved (ULONG)
rc (BOOL)
TRUE