Error when running macro to copy and insert row

Really stumped here. I just recently switched to Excel 2013 and some of my favorite macros are now generating errors. The odd part is that the macro will work perfectly when I first open my workbook, but if I make ANY changes to the table at all, then attempt to run the macro again, I receive Run-time error '-2147417848 (80010108)' Automation error The object involved has disconnected from its clients. The macro below was written to copy the topmost row of a table, insert the row immediately above (so it becomes the top row of the table), clear the contents of each cell (skipping over cells containing formulas), and return the active cell to the beginning of the row.

Sub Add_Row()
'
' Add_Row Macro
'

'
Application.ScreenUpdating = False
Range("A1").Select
ActiveCell.Offset(2, 0).Rows("1:1").EntireRow.Select
Selection.Copy
Selection.Insert Shift:=xlDown
ActiveCell.Select
Application.CutCopyMode = False
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 2).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 2).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 1).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, 2).Range("A1").Select
Selection.ClearContents
ActiveCell.Offset(0, -18).Range("A1").Select
Application.ScreenUpdating = True
End Sub

The macro always seems to break on Selection.Insert Shift:=xlDown. Again, I can run the macro successfully when I first open the workbook, but if I add the copied/cleared row at the top and add information to it, then try to run the macro to add another copied/cleared row for my next entry, I get the error. Additional pain is that it crashes my excel and I have to close all workbooks (saved or not) and reopen before I can resume working. I've tried searching all over the web for a solution to this. HELP!

Still getting hung up in the same spot. Is it the relative references that are causing the issue??