The student/postdoc site and IR website (internal/external) are great resources for any computer-related issue. If you’re still having computer troubles, see Amy Williams in the student support office during walk-in hours:

Email is for school-related business only (i.e. not to sell items, rent your apartment or bully classmates). Quid Pro Libro is a great way to sell books and there’s no great way to bully classmates.