It is shocking to see that my contents of Microsoft Outlook for Mac 2011 is wiped out for the Yahoo Account. I have the Microsoft outlook version 14.3.9 (131030) in my Mac Book Air and i am using this application for many years. This morning i have opened this application to realise that the Yahoo account is not in the MS Outlook and all the contents (including the messages, Rules, Contacts, Calendars etc for the only Yahoo account is empty. I did use this application last night without any problem. 

Could someone please guide me, how to get the contents back. My last backup was Sep 2014, which i can import it by setting up the account again. But, where and how to look for the actual and last contents in my computer. 

Many Thanks in advance.