To access the event platform, participants who registered and paid should have received a username/password pair by email. If you registered before October 11, then the email was sent on October 11 around 2 pm Japan time, and came from [email protected] with the subject "The 2021 IEEE Information Theory Workshop Dear ITW2021 participants". If you registered on or after October 11, then the email is sent soon after payment is confirmed. The username/password in the email looks something like UniversalLattices/2345. UN: and PW: are not part of the username/password.
Participants who paid can recover their username/password by logging into JTB's registration site, and finding their username/password on "My Page" under External System Login. This does not apply to persons who did not pay, primarily IT Society students who registered for free and did not pay a paper charge.