
I hate when that happens. That happened to mine 3 times but I still had access to it and finally changed the setting and password.... I hope that corrects that problem.
Before you change the password, I recommend you scan your computer with "stinger", "adaware" and your own antivirus software (at least once, maybe twice). Then change your password on hotmail.... and check your mail forwarding and vacation reply settings (they like to put their spam sales message within those replies and forwards as well).
Do a search for Hijacked Hotmail and you will see it has happened to many others .....
I think Hotmail's "ads" are partly to blame for that.
Good luck