I have a function to change a field name using DocMetaData.Field which always works, except for this new situation, which occurs after a CreateCopyOf. The error occurs in the second function.  Here is the code, which I hope is clear -

oLaserfiche.CopyDocumentWithTemplate(4, lfDoc, sLfRepository, lfDoc.FullPath, lfDoc.Name, "_Copy1")
iNewTocId = lfDoc.ID
oLaserfiche.UpdateLaserficheDocumentFieldValue("Type", sType, lfDoc)
 

'Called function #1 -
Public Sub CopyDocumentWithTemplate(ByVal ApplicationId As String,
          ByRef lfDoc As LFDocument,
          ByVal sLfRepository As String,
          ByVal FolderPath As String,
          ByVal FileName As String,
          ByVal NewFileNameSuffix As String)
Dim Application As String = String.Empty
Dim ReturnedMessage As String = String.Empty
Dim ActiveRepository As LFDatabase = Nothing
Dim CurrentDoc As LFDocument = Nothing
Dim ParentFolder As LFFolder = Nothing
Dim CopyDoc As New LFDocument
Dim iApplicationId As Integer = 0
Dim iTocID As Integer = 0

If FolderPath <> "" Then
 Try
  ActiveRepository = InitializeLaserficheConnection()
  CurrentDoc = New LFDocument
  CurrentDoc = ActiveRepository.GetEntryByPath(FolderPath)
  ParentFolder = ActiveRepository.GetEntryByPath(sLfRepository & FolderPath.Replace("\" & FileName, ""))

  CopyDoc.CreateCopyOf(CurrentDoc, FileName & NewFileNameSuffix, ParentFolder, True)
  CopyDoc.Update()
  lfDoc = CopyDoc

 Catch ex As Exception
  ReturnedMessage = "CopyDocumentWithTemplate. Error - " & ex.Source & "<br/> " & ex.Message
 Finally
  If Not CurrentDoc Is Nothing Then
   CurrentDoc.Dispose()
  End If
  If Not CopyDoc Is Nothing Then
   CopyDoc.Dispose()
  End If
  If Not ActiveRepository Is Nothing Then
   DisconnectLaserficheConnection(ActiveRepository)
   ActiveRepository = Nothing
  End If
 End Try
End If

End Sub

'Called function #2 -
Public Function UpdateLaserficheDocumentFieldValue(ByVal sFieldName As String, _
             ByVal sFieldValue As String, _
             ByRef lfDoc As LFDocument) As Boolean
Dim DocMetaData As LFFieldData = Nothing
Dim bReturn As Boolean = True

Try
 DocMetaData = lfDoc.FieldData()

 If Not DocMetaData.IsLocked Then
  'NEXT LINE HAS ERROR!
  DocMetaData.LockObject(Lock_Type.LOCK_TYPE_WRITE)
 End If
  'NEXT LINE HAS ERROR if I skip LockObject
 DocMetaData.Field(sFieldName) = sFieldValue
 DocMetaData.Update()

Catch ex As Exception
 ex.Source &= m_csModName & ".UpdateLaserficheDocumentFieldValue" & vbNewLine
 Throw
 bReturn = False

Finally
 If DocMetaData.IsLocked Then
  DocMetaData.UnlockObject()
 End If

End Try

Return bReturn
End Function

I greatly appreciate any help.

Howard