This appeared out of nowhere for us too, and coincided with the inability to edit the quantity or amount once we convert from estimate to invoice.  Anytime we need to change either of those (which is every invoice), we have to completely delete the line and reenter it.  It's insanely frustrating, and just randomly started happening from one day to the next.  Quickbooks is becoming more difficult to use by the day, it seems, new random changes constantly with no notice and no way to fix.  Please help.