Windows LiveMail 2011 takes 340GB out of 630GB of my hard drive most of it is the storage folders.

How can I find out is all the subfolders of the storage folders are necessary or are duplicate for recovery

process mainly ( which I had few recently)

How to most efficiently and without loosing mail I can deal with the situation?

Can I save all the emails to a different storage folders, Delete all the existing storage folders

and importing all emails back  WLM.