"We have been made aware that gmail has recently stopped accepting some emails from the USACO server -- e.g., for new accounts and password resets. If this issue is affecting you, please try adding usaco@usaco.org to your gmail contacts list. If you are still having issues, please notify the contest director, Brian Dean (bcdean@clemson.edu). If you have recently received an email from the USACO server such as a password reset email or an account creation email, consider starring it, so that gmail will hopefully treat USACO emails with better priority."