If Cell Value = Error, show MsgBox

Hi there,

I hope you are all well.

I need your help on a bit of a code I have.

I have a cell (on this case "Z18") that have a Vlookup formula. I want a MsgBox to show, if the value of the cell is Error only. This means that the value is not maintained on the Vlookup range.

I don't know the reference for Error. What I have is the following:

Private Sub Worksheet_Calculate()

If Range("Z18").Value = ERROR Then
End If
If MsgBox("Reference not found! Do you want to add it to database?", vbYesNo + vbQuestion, "Update file to Management") = vbNo Then End
UserForm1.Show
End If

So, in a nutshell, I want a MsgBox only if the value of the cell "Z18" is "#N/A".

The UserForm1 will open if users clicks "Yes" to add the reference to database.

Any ideas?

Your assistance will be highly appreciated.

Best regards,
Filipe Oliveira.

May be this....

Private Sub Worksheet_Calculate()

If IsError(Range("Z18").Value) Then
    If MsgBox("If MsgBox(Reference not found! Do you want to add it to database?", _
    vbYesNo + vbQuestion, "Update file to Management") = vbNo Then Exit Sub

    UserForm1.Show
End If

End Sub

Glad it helps you and thanks for the feedback