Hi @Tan Chong Beng
Thank you for posting your question in the Microsoft Q&A forum.
Here are some troubleshooting you can try to resolve it:
1. Adjust Settings in Microsoft Entra:
Go to Entra Admin Center Portal and find the resource "Microsoft Information Protection API" (Application ID: 40775b29-2688-46b6-a3b5-b256bd04df9f).
Navigate to Properties in the left sidebar.
Ensure that "Enabled for users to sign in?" is set to "Yes". If it show "No" , change to "Yes" then Save
2. If You Are Using Outlook Web:
Clear your browser's cache and cookies, then restart the browser.
Open an incognito/private browsing window and try accessing Outlook again.
Try logging out and then logging back into your Microsoft account.
3. If You Are Using Outlook Desktop App:
-Creating a new Outlook profile and reconnecting your account. For reference: Create an Outlook profile - Microsoft Support
-Open Outlook > go to File > Account Settings > Account Settings.
-Double-click your account and uncheck the box labeled "Use Cached Exchange Mode to download email to an Outlook data file."
-Close Outlook, restart your PC, and check if the error persists.
4. Contact IT Support for Further Assistance:
If none of these solutions work, I highly recommend contacting your IT Administrator to raise a support ticket via the Microsoft 365 Admin Center. A technical support agent will be able to assist you faster through a remote session, checking logs and configurations to apply the necessary fixes. For detailed instructions on how to get support, please refer to Get support - Microsoft 365 admin
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