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Sub Button1_Click()
   Dim ce As Range, i As Long
    Dim OutApp As Object
    Dim OutMail As Object
    Dim strto As String, strcc As String, strbcc As String
    Dim strsub As String, strbody As String

 c01 = "c:\users\mark\desktop\dgr.txt" 'change the path and the file name
    For i = 2 To Sheets("Sheet1").Range("a65536").End(xlUp).Row
        If Cells(i, 1).Value <> "" Then
            Set OutApp = CreateObject("Outlook.Application")
            OutApp.Session.Logon
            Set OutMail = OutApp.CreateItem(0)
        
            With Sheets("Sheet1")
                strto = .Cells(i, 4).Value 'column d
                strcc = .Cells(i, 5).Value
                strbcc = ""
                strsub = "Welcome to the Project " & " " & .Cells(i, 2)
                strbody = "Hi there," & vbCrLf & "We welcome you all to the project" & " " & .Cells(i, 2).Value & " " & _
                    "whatever...." & _
                    vbCrLf & vbCrLf & "Thank you."
            End With
    
            With OutMail
                .To = strto
                .CC = strcc
                .BCC = strbcc
                .Subject = strsub
                .Body = strbody
                .attachments.Add c01
                '.Send
                .display
                Cells(i, 1).Select
     With Selection.Font
        .Color = -16776961
        .TintAndShade = 0
    End With
            End With
    
            Set OutMail = Nothing
            Set OutApp = Nothing
        End If
  
    Next i
End Sub