Copy\Move Documents to another library based on column value

Dear All,
I have written ER to copy file from one library to another library, the document/file are moving and metadata (means
column values) are updating if i upload the documents with older extensions like .doc, .xls, .png, .gif etc.
if i use files with extensions like .docx, .xlsx, etc the document/file is moving but metadata (means column values 
are not updating.
Below is my code kindly please help me out.
                            SPList list = web.Lists["Test"];
                            SPListItem item = properties.ListItem;
                            string name = properties.ListItem["Status"].ToString();
                            string dept = properties.ListItem["To Department"].ToString();
                            string desc = properties.ListItem["Description"].ToString();
                            string comment = properties.ListItem["Comment"].ToString();
                            string letno = properties.ListItem["Letter No."].ToString();


                            DateTime date = Convert.ToDateTime(properties.ListItem["Date of Issue"].ToString());

                            SPUser oUserAuthor = properties.Web.EnsureUser("System Account");
                            SPUser oUserModified = properties.Web.EnsureUser("System Account");

                            System.DateTime dtCreated = item.File.TimeCreated;
                            System.DateTime dtModified = item.File.TimeLastModified;

                            if (name == "Approved" && dept == "Sales and Marketing")
                            {
                                Hashtable ht = new Hashtable();
                                ht.Add("Approval Status", name);
                                ht.Add("Department", dept);
                                ht.Add("Comment", comment);
                                ht.Add("Letter No.", letno);

                                ht.Add("Date of Receiving", date);
                                ht.Add("Summary", desc);

                                SPFile newFile = list.RootFolder.Files.Add(item.File.Name, item.File.OpenBinary(), ht, oUserAuthor, oUserModified, dtCreated, dtModified, true);

                                newFile.Update();
                            }
i have attached the document for your overview.
Many thanks in advance.
Regards,
Ravi Kumar. S