Color- When Copying Excel Sheet To Other Workbook

I Have a macro which combines five excel sheets from five workbook into single worbook with five tabs containing five excel sheets.Everything is fine except that color of all five excel sheets is totally changed in the combined excel workbook.I tried this manually i.e copying excel sheet from each workbook and pasting the same in the new work book.

Here also color comes correct in only one excel sheet and rest all sheets color is lost.Please any one knowing solution to this problem explain. macro is used is shown below

Sub CopySheets()
Dim fileFolder As String
Dim fso, fsoFiles, f1
Dim w1 As Workbook
Dim w2 As Workbook
Dim ws As Worksheet
Dim i As Integer
Dim flag As Integer
Set w1 = Application.Workbooks.Add
Application.DisplayAlerts = False
Application.ScreenUpdating = False

fileFolder = "D:documents est est" '