I haven't used my account in a few years and Steam have upgraded their security system, so even though I know my username and password, they won't let me access my account because I can't remember the email address that I used. I've spent days emailing back and forth with their support and they just make stupid excuses. They can see nobody has accessed the account in years back still claim to be "protecting the owner", no you're just angering the owner and making sure they don't spend any more money with you.