Hi, Chica9000!
First of all welcome to Chandoo's website Excel forums. Thank you for your joining us and glad to have you here.
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And about this question in particular...
Give a look at this file:
https://dl.dropboxusercontent.com/u/60558749/Open%20Excel%20template%20and%20autosave%20file%20with%20date%20%28for%20Chica9000%20at%20chandoo.org%29.xlsm
This is the code:
-----
[pre]
Code:
Option Explicit
Private Sub Workbook_Open()
'
' constants
Const ksWSLastNo = "Hoja1"
Const ksLastNo = "ParamLastNo"
Const ksExtensionMacro = ".xlsm"
Const ksExtensionNormal = ".xlsx"
Const ksSeparator = "_"
Const kiDigits = 8
'
' declarations
Dim wb As Workbook, ws As Worksheet, rng As Range
Dim I As Long, A As String
'
' start
With Application
.DisplayAlerts = False
.ScreenUpdating = False
End With
'
' process
' number
Set rng = Worksheets(ksWSLastNo).Range(ksLastNo)
With rng
I = .Cells(1, 1).Value
I = I + 1
.Cells(1, 1).Value = I
End With
Set rng = Nothing
' old wb
With ThisWorkbook
' save
.Save
' source
Set ws = .Worksheets(ksWSLastNo)
' new wb
Set wb = Workbooks.Add
' name
A = Left(.Name, Len(.Name) - Len(ksExtensionMacro)) & ksSeparator & _
Format(Now(), "yyyy-mm-dd") & ksSeparator & _
Format(I, String(kiDigits, "0")) & ksExtensionNormal
End With
' new wb
With wb
' paste in target
ws.Copy .Sheets(1)
' extra worksheets
For I = .Worksheets.Count To 2 Step -1
.Worksheets(I).Delete
Next I
' rename ws
.Worksheets(1).Name = ws.Name
' save
.SaveAs ThisWorkbook.Path & Application.PathSeparator & A, xlWorkbookDefault
End With
' old wb
With ThisWorkbook
' close
.Close
End With
'
' end
Set ws = Nothing
Set wb = Nothing
With Application
.ScreenUpdating = True
.DisplayAlerts = True
End With
'
End Sub
[/pre]
-----
Just advise if any issue.
Regards!