Long ago I created a gmail account and checkmarked "remember me", so when I sign in now it autopopulates my gmail and password (similar to how it does when you sign in to this forum if you checkmarked "remember me"). I also created a youtube account with this gmail. Now I'm using proxies to create new gmail and youtube accounts, but when I go to Google it autopopulates that one gmail everytime. I always have to click "sign in with a different account" to go and register a new one. How is Google identifying my computer even when I'm using proxies? I'm using Firefox and I click "History" then clear all my cookies, history, cache etc. I then go offline and use CCleaner, then get back online and sign in to a new proxy with a new location and new ip I've never used before. Then I go to Google again and click "sign in" and there's that original gmail still autopopulating at the sign in screen. Thanks for anyone who can help me.