Please check the following announcement for the latest information on this problem. Information before it became an FAQ is also available.
How to resolve the problem when authenticating Microsoft Office products on a satellite device

On Windows Remote Access or Satellite Terminal of The Zengaku Computer System When starting Office, the screen may go blank at the authentication process and you may not be able to proceed.
In addition, you may be asked to perform the same authentication operation several times.

If you encounter such a problem, please try the following operations.

Solution #1 (Added 6/9/2023)

You can improve the situation by disabling the multi-factor authentication setting at the following site.

Academic Computing Communications Center,University of Tsukuba
Cloud mail service authentication setting system (Microsoft 365)
https://m365setting.u.tsukuba.ac.jp/

Even if the authentication appears to be disabled on the screen, the authentication behavior may be improved by enabling it once and then disabling it again.

Alternatively, the error no longer occurs when the multi-factor authentication settings are completed to the end.

Solution #2

1. sign out from the Office application
   If your name appears in the upper right corner of the Word or Excel screen, you are signed in to the Office application.
   Click your name, and the “Sign Out” item will appear.
   When the message “Delete Account” is displayed, click “Yes” to proceed.
2. Close all Office applications.
3. Open a browser and go to the Microsoft 365 site and sign in with your account.
   Enter your @u email address for your account and the password you have set for Microsoft 365.
   *This is different from the password for The Zengaku Computer System.
   *If the “More information required” screen appears after entering your account and password, click “Next.
4. Confirm that the authentication operation is complete and the Microsoft 365 main screen appears before proceeding to the next step.
   In the following steps, please proceed with the operation while signed in to the above browser until you can confirm sign-in with the Office application.
5. On the Windows Remote Access or Satellite terminal, start the Office application again.
   You will be asked to sign in. Enter your @u email address for the account and the password you set for Microsoft 365.
   Once the authentication process is successfully completed, you will be able to use the Office app.

Solution #3 (Added 7/28/2023)

Change the “Account Settings” in Windows.
For details, please refer to the following.
Microsoft Product Authentication Failures on Terminals and Remote Access Service Solution #3

If the above steps do not improve the situation, please try initializing your profile.
Windows profile initialization