Unhide Rows/Columns Of Used Data Range

I have a Sheet which gathers data from another Sheet in the same Workbook, then uses that data to produce more output. However at it's smallest it is only 2 rows of data deep and 2 columns of data wide, and at it's greatest it is 100 rows deep by 48 columns wide.

I would like to display only the relevant output by "Unhiding" the completed rows and columns.

After headings etc the rows start at 28 and the columns at N.

I have written the following which works for the rows but nothing happens with the columns,

Private Sub Worksheet_Activate()
Dim MyRange As Range
Dim MyRow As Integer

Set MyRange = Range("a28")

MyRange.Select

Do

MyRow = MyRange.Row
If MyRange.Value > 0 Then
Rows(MyRow).Select
Selection.EntireRow.Hidden = False
End If

Set MyRange = MyRange.Offset(1, 0)
Loop Until MyRow = 128
End Sub...