sign into Live Mail & recovery of all my folders that are lost.

Everytime I wanted to sign into Windows Live Mail, I would get the message that I couldn't sign in because password or username were invalid.  My mail would still come through & Icould go on as usual.  I called my ISP thinking that was the problem.  I was told to do something that completely got rid of all my folders & sub folders.  My ISP has a webmail which gets my emails 1st, & then windows Live mail receives them.  I did something which transferred the folders from webmail to live mail exactly as the webmail had them.  This was not the same as my folders in Live mail.  Are my folders inLive mail lost or how can I get them back?  and will I ever be able to sign in to Wikndows again?