date showing in USA format following export to excel

'Export the Columns to excel file
For Each dc In datatableMain.Columns
    colIndex = colIndex + 1
    oSheet.Cells(1, colIndex) = dc.ColumnName
Next

'Export the rows to excel file
For Each dr In datatableMain.Rows
    rowIndex = rowIndex + 1
    colIndex = 0
    For Each dc In datatableMain.Columns
        colIndex = colIndex + 1
        oSheet.Cells(rowIndex + 1, colIndex) = dr(dc.ColumnName)
        'ProgressBar.PerformStep()
        Progresslbl.Text = "Total rows exported = " & rowIndex & " out of " & MaxRows2
        Me.Refresh()
    Next
Next

For Each item As ListViewItem In DocumentedLst.SelectedItems
    Ref.Text = item.SubItems(0).Text
    fwords = Ref.Text.Split(New Char() {" "c})

    For Each row In myDataTable.Rows
        Dim tempvalue As String = ds.Tables("FullDetails").Rows(inc)("SMART").ToString()

        words = tempvalue.Split(New Char() {" "c})
        If words(0) = fwords(0) Then
            fwords = tempvalue.Split(New Char() {" "c})
            foundRow = row
        End If
        inc = inc + 1
    Next row

    If item.Selected = True Then
        Ref.Text = fwords(0)

        Retrieve.Visible = False
        Submit.Visible = True
        Delete.Visible = True

        If foundRow IsNot Nothing Then

            If Mid(fwords(1), 1, 2) = "IM" Then
                IM.Text = fwords(1)
                Server.Text = fwords(2)
            Else
                IM.Text = ""
                Server.Text = fwords(1)
            End If

            LocationName.Text = foundRow(3).ToString()
            StartTime.Text = foundRow(4).ToString() ****** This is displaying as USA format after the export has completed and the form is reloaded. If I exit the application and relaunch it shows correctly. The only only appears after the export. ******