Today I wanted to check my emails but unfortunately after restarting my computer when I started outlook it came blank. All my 17 gig emails had disappeared. I checked in documents folder there was a new folder named as microsoft user data. Before I had Main Identity folder only. 

Each time I start outlook it wants to build a new identity folder and this folder always creates Microsoft User Data named file and under this there is Main identity, but it keeps creating new identity data base folder.

finally I copied all data to this folder and fresh started the outlook but this time it gives me the error message that these data are older version and I should rebuild identity by using the older version.

I don`t know what to do.

Can any one help me.