@ 123sonya123
We’re aware of this issue and we found out that Malware is one of the causes. I suggest that you check out this link to learn more about this issue:
http://windowslivehelp.com/solutions/safety/archive/2009/04/29/recent-reports-of-account-hijacks.aspx
FYI: I’ve moved your post here at the Accounts and Passwords forum.