You can use the junk e-mail filter to help decrease the amount of junk e-mail that appears in your Inbox.
Sign in to the Windows Live Hotmail website with your Windows Live ID (The user name and password that you use to sign in to any Windows Live, MSN, or Office Live sites and services. If you have a Passport Network, Hotmail, or Messenger account, you can use it as your Windows Live ID.) .
In the upper-right corner of the page, click Options, and then click More options.
Under Junk e-mail, click Filters and reporting.
Under Filters and reporting, select the options that you want, and then click Save.
Notes
If you choose Exclusive for your junk e-mail filter, only messages from e-mail addresses on your Contacts or Allowed senders lists appear in your Inbox. Messages from senders not on those lists are automatically sent to the Junk e-mail folder.
You should occasionally check your junk e-mail folder to make sure that good messages are not sent to there by mistake.