Thank you very much.
It worked. The only minor thing I did is change as snippet to the following:
(Target.Value = 1 Or Target.Value = 2) And _
(Target.Offset(, -1).Value < "" _
And Target.Offset(, -1).Value = 0)
because it was giving the alert when the cell to the left was blank before
this change.
Thanks again.
Wissam
"Mike H" wrote:

Hi,

I think i've understood the question , try this. Right click your sheet tab,
view code and paste this code in

Private Sub Worksheet_Change(ByVal Target As Range)
If Target.Cells.Count 1 Or IsEmpty(Target) Then Exit Sub
If Not Intersect(Target, Range("C1:M41")) Is Nothing Then
If Target.Value = 1 Or Target.Value = 2 And _
Target.Offset(, -1).Value < "" _
And Target.Offset(, -1).Value = 0 Then
MsgBox ("You entered " & Target.Value & " After a zero")
End If
End If
End Sub

--
Mike

When competing hypotheses are otherwise equal, adopt the hypothesis that
introduces the fewest assumptions while still sufficiently answering the
question.


"wissam" wrote:

Hi.

I have a range of cells (C42:M42) where the user can enter values of 0,1,or
2 only (set up via data validation).

I need help with a code to do the following: if the worksheet user enters a
value or changes the value in a cell in the above range (C42:M42), then excel
would automatically check ( via a macro?) the value entered and compare this
value to the value present in the previous cell on the same row. If the value
entered is 1 or 2, and the value in the previous cell was 0, then it would
give a msgbox alert.

Any help is appreciated.

Thank you very much.