I think this will work for you. I changed a to a module-level variable.
You could also make it a static variable in the procedure. I changed your
If Then to a Select Case:

Option Explicit
Dim a As Integer
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Select Case Target.Address
Case "$O$22", "$D$9:$E$9", "$C$19", "$C$21"
a = ActiveWindow.Zoom
ActiveWindow.Zoom = 120
Case Else
If a = 0 Then
a = ActiveWindow.Zoom
End If
ActiveWindow.Zoom = a
End Select
End Sub

hth,

Doug

"Ndel40" wrote in message
...
I'm using tab code to zoom in on a cell when it is selected. Once the
user
leaves the zoomed cell, I would like to return to the previous value of
the
zoom property before it was set to 120.

For example. the user is in cell A1 and they set the zoom value to 75.
They
then select cell O22 and the zoom value is automatically set to 120. When
the leave cells O22, I would like to have the value of zoom set back to
75.

I realize I could set this manually with ActiveWindow.Zoom = 75, however,
most users have different zoom preferences, so I would like it to go back
to
what they had set.

My code is below...

Thanks

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Dim a As Integer

a = ActiveWindow.Zoom
Range("a1").Value = a


If Target.Address = "$O$22" Then
ActiveWindow.Zoom = 120

ElseIf Target.Address = "$D$9:$E$9" Then
ActiveWindow.Zoom = 120

ElseIf Target.Address = "$C$19" Then
ActiveWindow.Zoom = 120

ElseIf Target.Address = "$C$21" Then
ActiveWindow.Zoom = 120

Else
ActiveWindow.Zoom = a
End If
End Sub