I have had my account for years.  In the last few days, when I cc or bcc myself on an e-mail, I receive a message stating, delivery, recipient failure, especially if there is an attachment.  If I just say, hi; no problem.  Is this related to an e-mail I receive lately stating, your outlook box is getting full; even though I "dump" a lot, so it is not full.  I just had someone send me an e-mail, and they received the same message, recipient failure.