Forgot my xbox gamertag email?

hadd it for 4 years but i called xbox and they sed i have too anwser the secret qustion i put but i dont remember how i spelled it or put it..but recoverd it on my friends hhouse one te and then brong it to myharddrive then sold my harddrive..then i goo too my friends house and see my profile there but cant goo online with it can find the email threw there please HeLPPPP