Embed files needs to sign in every time

Hello Wang, Qianqian CN/SHG EXT

Thank you for reaching out to the Q&A Forum and for providing the detailed information.

Regarding the behavior you mentioned, may I ask whether this issue happens with all files, or only with specific files? If it occurs only on certain files, could you please review the permissions or the permission inheritance on those files? Sometimes custom permissions or broken inheritance may cause inconsistent access behavior.

Based on my research, some suggestions indicate that this behavior may stem from browser cookie policies or conditional access policies. When you have time, could you help me check those two areas as well?

Additionally, I’d like to confirm whether the sign‑in prompt appears only on one browser, or if it persists across different browsers for the same account. For example, if the affected user signs in using another browser, does the issue still occur?

You may also find this article helpful: “How to handle third‑party cookie blocking in browsers” It explains how blocked cookies can affect authentication inside embedded content.

I hope this information is helpful. Please note that initial responses may not always contain the right solution, but we will continue working together until we find the right answer.

Looking forward to your reply.

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These files cannot be shared to everyone, only to specific people.

And some users do not neeed to sign in evey time, but some needs. I think it is not the file setting.

The repeated sign-in prompt when viewing embedded Excel files usually occurs because the embedded content requires authentication and the browser cannot reuse or send the necessary cookies or session to Microsoft 365.

For public, no‑sign‑in viewing of embedded workbooks, configure the source file’s sharing and embed settings so that anonymous access is allowed:

1. In SharePoint Online or OneDrive for Business, locate the workbook.
2. Open the More menu (...) next to the workbook and select Share.
3. Share the workbook with Everyone (or Everyone except external users if Everyone is blocked by admin) and set permission to Can view.
4. Ensure the Require sign-in box is unchecked so that anonymous users can open the workbook without authenticating.
   • If the Require sign-in box is removed or forced to True by policy, anonymous access is blocked and users will always be asked to sign in; in this case, an admin must change the policy if sign‑in‑free embedding is required.
5. Use the embed HTML generated from OneDrive/SharePoint (for example, via </> Embed or File > Share > Embed) in the external application.

If the workbook is not shared for anonymous access, or if the tenant admin blocks anonymous links, users will be prompted to sign in each time the embedded frame loads, especially in private/incognito modes or when third‑party cookies are blocked.

References:

• Embed your Excel workbook on your web page or blog from SharePoint or OneDrive for Business
• How to add an embedded document or picture into a webpage
• Troubleshooting startup or sign-in issues for Power Apps