Hi @SY ,
Welcome to Q&A forum!
First, please update your Office to the latest version.
- Do all Office Apps have this issue? Please check other Apps, such as Excel and PowerPoint.
- Besides, please check if you could open the Office Store app normally.
Based on the error message, the Office Store add-in may be disabled by the administrator.
Please sign in to your administrator account to Office365 Portal, and then go to Admin> Settings> Service & add-ins> User owned apps and services> Ensure “Let users access the Office Store”.
Does Azure need to be configured for these users to access the apps from the organization?
< Please refer to: Prerequisites for Microsoft Store for Business and Education.
Reference: Roles and permissions in Microsoft Store for Business and Education
Hope the information could be helpful to you. Any updates, please let me know.
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