Private Sub CommandButton1_Click()
'Define an excel object
Dim objExcel As Object

'Open the excel sheet which needs to be changed
Set objExcel = CreateObject("Excel.Application")
objExcel.Workbooks.Open Filename:=Application.GetOpenFilename

'Replace text of a cell in the 'Risk, Issue Metrics' worksheet
objExcel.Sheets("Risk, Issue Metrics").Select
objExcel.Cells(9, 1).Value = "No. of minor risks open (i.e. with risk
exposure between 3.5 and 0)"

'A subroutine is located in the same worksheet. This needs to be updated
with a new code here
'How do it do it?

'Save updated excel sheet and close it
objExcel.Workbooks(1).Save
objExcel.Workbooks.Close
objExcel.Quit
Set objExcel = Nothing
End Sub