How can they hack my account ?
It's very simple and stupid. The hacker get to the hotmail and claims that he forgot the password and answer the stupid questions asked to get the password back. These questions are stupid because they're very easy to guess the answer. "What is your mother's birth place" Imagine that!! If you're a Californian there is a 80% chance that your mother's Californian too. Most people pick the easiest question because they're in a rush but they didn't know that they maid a bad choice !
How to protect my IM account from being hacked ?
First of all make a strong password : a long one with different characters and punctuation marks. Make it meaningful just for you. Let's have an example. Pick your best car name or pet and break it into syllables and write every syllable with a number:
my1best2car3name4
Then break the syllables with other characters like "; : | (" the result will be like : my1;best2:car3!name4(
This will make a good password. Don't give to anybody, don't save it down on your computer and never write it down !
Second, Never use these stupid questions to get your password . Use alternate email address , once you forget the password they'll email for you and make sure both email accounts are secure!!