Since the RecordCount property is known to be unreliable unless you move to
the end of the recordset, try replacing

If rst.RecordCount > 0 Then

with

If rst.EOF = True Then

(either that, or put rst.MoveLast before you check the Count property)

If that still doesn't work, put a Debug.Print strSQL in your routine after
you've set its value. Go to the Debug window (Ctrl-G) and see whether the
SQL looks okay. Copy it into a new query and run it. What result do you get?

Hi Tom,

Perhaps you can try a different approach. Create a combined field index
(unique / no duplicates) using the three fields: StoreID, Product and
Squantity. Then add the following code to the form:

Private Sub Form_Error(DataErr As Integer, Response As Integer)
   Select Case DataErr
   Case 3022
       MsgBox "This item has already been added." & vbCrLf & _
              "You cannot create duplicates.", _
               vbOKOnly + vbInformation, "Item Already Added..."
       Me.Undo
       Response = acDataErrContinue
   Case Else
       Response = acDataErrDisplay
   End Select

End Sub

Also, your previous message showed this:

Private Sub Exit_Click()
DoCmd.Close
End Sub

I recommend that you change it to read as follows, assuming this is a bound
form:

Private Sub Exit_Click()

   If Me.Dirty = True Then
        Me.Dirty = False
   End If

   DoCmd.Close acForm, Me.Name

End Sub

Here is the reason that I make this recommendation to set Dirty = False:

    Losing data when you close a form
    http://allenbrowne.com/bug-01.html

Specifying "acForm, Me.Name" will help prevent any possibility of the wrong
object getting closed. While this is usually a rare occurance, it is easy
enough to add this little bit of insurance.

Tom Wickerath
Microsoft Access MVP
https://mvp.support.microsoft.com/profile/Tom
http://www.access.qbuilt.com/html/expert_contributors.html
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