I cannot delete unknown Hotmail contacts

I have several contacts on my Windows Live email account whom I never added and whom I cannot delete.  These people never requested to be added, they simply are.  They show up when I begin entering a name to send an email to, and they are also there in the official contact list (not just the drop-down one).  I know how to delete contacts.  However, when I try to delete them, they magically re-appear in a matter of seconds, less than one minute.  Therefore, I cannot delete them.  I have checked requests to be added to my group or contacts and they are not there, that is clean and empty.  These unknown contacts have been there for awhile and I finally decided to get rid of them, but apparently I can't.  Does anyone have a solution or suggestion for this problem I am experiencing?
Thank you.

PS: I am not using Outlook or anything like that, I just use a normal Internet browser, go to Hotmail.com, and then to my email from there.