I don't have Boxbe mail so I can't access their system to provide you with detailed instructions, but please review this page
and make sure you have logged into Boxbe to close your Boxbe account.
If you have already done so, try doing it again and make sure you get confirmation that your account is closed. See this page
if you have any difficulty, or it doesn't work, and submit a written request to Boxbe support to close your account.
Additionally, it's possible that any organizations that you subscribed to with your Boxbe address will have to be contacted and change the email address or unsubscribe to them.
If that doesn't work out, I'm afraid the only alternative I can suggest is to start fresh with a new address. You can keep the old address going for a bit until your contacts have had time to get used to the new one, but this can be a great way to eliminate spam and junk mail. If you wish, you can set up the old email account to forward mail to another new address to keep track of any lingering contacts for a few monthes, then close the old yahoo account down and with it will go the Boxbe dregs.
These email issues can be frustrating. Try downloading the email with the attachment that won't open onto your computer with and email server like Outlook or Outlook express or whatever is appropriate to your system OS, and see if you can't open the attachment then. Some online email servers will not support the reading of attachments online.
I hope this information allows you to resolve this issue. If you need further assistance, please post back with a comment to this thread.
If I've managed to answer your question or solve a problem, please take just a moment to rate this post....thanks!