static void CreateFolder(ExchangeServiceBinding esb, FolderIdType fiFolderID, String fnFldName)
    {
        // Create the request
        FolderType folder = new FolderType();
        folder.DisplayName = fnFldName;

        TargetFolderIdType targetID = new TargetFolderIdType();
        targetID.Item = fiFolderID;

        CreateFolderType createFolder = new CreateFolderType();
        createFolder.Folders = new FolderType[] { folder };
        createFolder.ParentFolderId = targetID;

        try
        {
            // Send the request and get the response
            CreateFolderResponseType response = esb.CreateFolder(createFolder);

            // Get the response messages
            ResponseMessageType[] rmta = response.ResponseMessages.Items;

        }
        catch (Exception e)
        {
            string problem = e.Message;
        }
    }