Binaryworld - GetFileOwner - Get the owner of an NTFS file ... [ VB -> Files & Folder ]

Private Declare Function GetFileSecurity Lib "advapi32.dll" Alias _
  "GetFileSecurityA" (ByVal lpFileName As String, ByVal RequestedInformation _
  As Long, pSecurityDescriptor As Byte, ByVal nLength As Long, _
  lpnLengthNeeded As Long) As Long
Private Declare Function GetSecurityDescriptorOwner Lib "advapi32.dll" _
  (pSecurityDescriptor As Any, pOwner As Long, lpbOwnerDefaulted As Long) As _
  Long
Private Declare Function LookupAccountSid Lib "advapi32.dll" Alias _
  "LookupAccountSidA" (ByVal lpSystemName As String, ByVal Sid As Long, _
  ByVal name As String, cbName As Long, ByVal ReferencedDomainName As String, _
  cbReferencedDomainName As Long, peUse As Long) As Long
Private Declare Function GetWindowsDirectory Lib "kernel32" Alias _
  "GetWindowsDirectoryA" (ByVal lpBuffer As String, _
  ByVal nSize As Long) As Long

Const OWNER_SECURITY_INFORMATION = &H1
Const ERROR_INSUFFICIENT_BUFFER = 122&
Const MAX_PATH = 255

' return the name of the file owner
'
' runs over Windows NT or 2000, and works only with files in NTFS partitions

Function GetFileOwner(ByVal szfilename As String) As String
  Dim bSuccess As Long    ' Status variable
  Dim sizeSD As Long     ' Buffer size to store Owner's SID
  Dim pOwner As Long     ' Pointer to the Owner's SID
  Dim ownerName As String  ' Name of the file owner
  Dim domain_name As String ' Name of the first domain for the owner
  Dim name_len As Long    ' Required length for the owner name
  Dim domain_len As Long   ' Required length for the domain name
  Dim sdBuf() As Byte    ' Buffer for Security Descriptor
  Dim nLength As Long    ' Length of the Windows Directory
  Dim deUse As Long     ' Pointer to a SID_NAME_USE enumerated type
                ' indicating the type of the account

  ' Call GetFileSecurity the first time to obtain the size of the buffer
  ' required for the Security Descriptor.
  bSuccess = GetFileSecurity(szfilename, OWNER_SECURITY_INFORMATION, 0, 0&, _
    sizeSD)
  ' exit if any error
  If (bSuccess = 0) And (Err.LastDllError <> ERROR_INSUFFICIENT_BUFFER) Then _
    Exit Function

  ' Create a buffer of the required size and call GetFileSecurity again
  ReDim sdBuf(0 To sizeSD - 1) As Byte
  ' Fill the buffer with the security descriptor of the object specified by
  ' the
  ' filename parameter. The calling process must have the right to view the
  ' specified
  ' aspects of the object's security status.
  bSuccess = GetFileSecurity(szfilename, OWNER_SECURITY_INFORMATION, sdBuf(0), _
    sizeSD, sizeSD)
  ' exit if error
  If bSuccess = 0 Then Exit Function

  ' Obtain the owner's SID from the Security Descriptor, exit if error
  bSuccess = GetSecurityDescriptorOwner(sdBuf(0), pOwner, 0&)
  If bSuccess = 0 Then Exit Function

  ' Retrieve the name of the account and the name of the first domain on
  ' which this SID is found. Passes in the Owner's SID obtained previously.
  ' Call LookupAccountSid twice, the
  ' first time to obtain the required size of the owner and domain names.
  bSuccess = LookupAccountSid(vbNullString, pOwner, ownerName, name_len, _
    domain_name, domain_len, deUse)
  ' exit if any error
  If (bSuccess = 0) And (Err.LastDllError <> ERROR_INSUFFICIENT_BUFFER) Then _
    Exit Function

  ' Allocate the required space in the name and domain_name string variables.
  ' Allocate 1 byte less to avoid the appended NULL character.
  ownerName = Space(name_len - 1)
  domain_name = Space(domain_len - 1)

  ' Call LookupAccountSid again to actually fill in the name of the owner
  ' and the first domain.
  bSuccess = LookupAccountSid(vbNullString, pOwner, ownerName, name_len, _
    domain_name, domain_len, deUse)
  If bSuccess = 0 Then Exit Function

  ' we've found a result
  GetFileOwner = ownerName

End Function