Q. What does the error message "This username may be incorrect. Make sure you typed it correctly. Otherwise, contact your admin." mean when signing in to Microsoft 365 Copilot?
A. This may occur if the username is mistyped or if a THERS email address (@mail.f.thers.ac.jp, @s.gifu-u.ac.jp, @s.mail.nagoya-u.ac.jp, @mail.a.thers.ac.jp) was entered instead of the correct Microsoft 365 account.
On the Microsoft sign-in screen, please enter your THERS account (e.g., ab.12c.3456@f.thers.ac.jp, @s.thers.ac.jp, or @a.thers.ac.jp).
Reference: An error occurs even when THERS account is entered at the time of sign-in.