[AccessD] Duplicates on Two Values

This gives me an error. I think because I have the text fields ''''
messed up.

 

  If Not IsNull(ItemName) And Not IsNull(ItemDesc) Then

    If DCount("ItemName", "tbl_ItemMain", "ItemName = '" & [ItemName] &
"'and "ItemDesc = '" & [ItemDesc]) > 0 Then

        MsgBox "You have entered a ItemName and ItemDesc that already
exists"

        ItemName.SetFocus

        ItemName.Undo

    End If

End If