Multiple API calls crashing NT

[docHoliday]

I and a VB buddy have done some independent digging though a bit of code used to open the contents of a machine into a Tree View control using API calls. The problem is the app crashes in NT because more than 1 API call are being made to the same DLL at the same time. They are inside a DO loop, and the it fires an API call it's first time through, but doesn't seem to close it before the second Loop. What I need help with now is identifying which API call made within this function may be persisting through the loop to the next interation.

Here's the function at fault. Again, any help is greatly appreciated. If anyone would like the entire VBP file to see it in action, you can download it here Message Posted in genral Questions thread

And now the error filled code:

'This function simply checks a directroy to see if it has any sub directories
'It returns the first sub dir name and then exits
Function HasSubDirs(ByVal sStartDir As String) As String

Dim lpFindFileData As WIN32_FIND_DATA, lFileHdl  As Long, lRet As Long
Dim sTemp As String
On Error Resume Next
If sStartDir = "" Then Exit Function

If Right$(sStartDir, 1) <> "\" Then sStartDir = sStartDir & "\"
sStartDir = sStartDir & "*.*"
lFileHdl = FindFirstFile(sStartDir, lpFindFileData)

If lFileHdl <> 0 Then
    Do Until lRet = ERROR_NO_MORE_FILES
        If (lpFindFileData.dwFileAttributes And FILE_ATTRIBUTE_DIRECTORY) = 16 Then
            sTemp = StripTerminator(lpFindFileData.cFileName)
            If sTemp <> "." And sTemp <> ".." Then
                HasSubDirs = StrConv(sTemp, vbProperCase)
                Exit Do
            End If
        End If
        lRet = FindNextFile(lFileHdl, lpFindFileData)
        If lRet = 0 Then Exit Function
    Loop
End If
lRet = FindClose(lFileHdl)
End Function