My Outlook for Mac 2011 IMAP email accounts DOWNLOADED and DELETED all of my emails from my host/server, and crashed -- went blank.  I lost everything.  I was able to restore from a backup to my laptop (but not the server), but lost changes during the down time.  How could this happen with IMAP accounts and how can I keep it from happening again?

The creation of IMAP accounts is supposed to guarantee that there will always be two copies of my emails -- one on my laptop's Outlook and one on my host's server.  However, although I had configured Outlook for IMAP accounts, it downloaded the original emails before and/or as a part of the crash.