I have a glitch in my code. The purpose of the code is to protect the
formulas in cells on Sheet1, while still allowing a specific text entry
("Ex"). And if a user then chooses to delete the "Ex" the cell will revert
back to the original formula, by retrieving it from Sheet3.

My code works well in single cells. But I have in some merged cells (e.g.,
E5 is merged from E5 and E6), and there is a glitch in the code. In those
cells, pressing the delete key actually deletes the contents of the cells,
and results in an error. If I delete the cell by pressing 'backspace' and
then 'enter' the code works as expected.

Here is my code:
If Application.Intersect(Target, Range("E5:E49")) Is Nothing Then
Exit Sub
End If
If Target.Value < "Ex" Then
Application.EnableEvents = False
Target.Formula = Sheets("Sheet3").Cells(Target.Row,
Target.Column).Formula
Application.EnableEvents = True
End If
Exit Sub