Cancel unused email address/domain used to send salacious mail to my Outlook account.

How can I cancel an old Address and Domain which I have not used for years.  I am receiving very salacious junk mail to the old address/domain ( *** Email address is removed for privacy ***).  Please help as my young grandsons use my computer when they visit; and needless to say, I waste a lot of time checking the JUNK mail to ensure non-junk mail is in the JUNK folder.