Yesterday, I can read all my messages.  Today, the emails I did not delete are still listed in the inbox but some of them have their contents replaced by the error: 'Message Cannot Be Found'.  Seems to happen at random to random messages.  Very rarely, there will be an additional sentence: 'To view the message anyway, click here' - and clicking on that link restores the message content.  But most do not have that link and the content is gone.