Most of the times comments are used for internal purpose. This need not go with the workbbok, here is the way to remove it
Sub Remove_Comments_From_WKBK()
'
' Remove Comments from Excel 2007 Workbook
'
'
ActiveWorkbook.RemoveDocumentInformation (xlRDIComments)
End Sub
If you want the same for Excel 2003 and before here is the code
Sub Remove_Comments_From_WKBK_2003()
'
' Remove Comments from Excel 2003 Workbook
'
'
Dim wks As Worksheet
Dim cmnt As Comment
For Each wks In ActiveWorkbook.Sheets
For Each cmnt In wks.Comments
cmnt.Delete
Next cmnt
Next
End Sub