Лучше использовать следующий код:
Dim Check1
Private Sub Worksheet_Activate()
Check1 = 0
End Sub
Private Sub Worksheet_Change(ByVal Target As Range)
If Target.Address = "$A$1" Then
Range("A1"

.Copy
ActiveSheet.Paste Destination:=Worksheets("Sheet1"

.Range("C1"

End If
End Sub
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
On Error Resume Next
Set myRange = Intersect(Range("A1:A1"

, Target)
If Not myRange Is Nothing Then
Check1 = 1
Else
If Check1 = 1 Then
Range("A1"

.Copy
ActiveSheet.Paste Destination:=Worksheets("Sheet1"

.Range("C1"

Check1 = 0
End If
End If
End Sub