A group of Microsoft Products and technologies used for sharing and managing content, knowledge, and applications.
Good day @Bhawna Sharma, and I appreciate the clear explanation of your concern.
Just to gently clarify before we go any further, this is a user‑to‑user support forum. I don’t have the ability to access or investigate individual accounts because this is a user-to-user support forum. Moderators and contributors, including external Microsoft employees, do not have access to internal systems or the ability to directly take action on Microsoft product features. However, I truly hope I can help review your situation, offer some guidance, and support you in finding the right next steps as best as possible.
From your description, the behavior you are experiencing aligns with recent updates where SharePoint and OneDrive sharing now follow Microsoft Entra B2B policies, which have been rolling out by default since May 2026. The error AADSTS90072 typically indicates that the external user has not yet been added as a guest, or that the invitation process is being blocked by tenant settings.
Please see the following workarounds that will help you verify the issue:
Note: The steps below require action from your organization’s IT admin; if you’re an end user, please contact them and feel free to share this information. In case you do not know who is your IT admin, kindly refer to this article: How do I find my Microsoft 365 admin? - Microsoft Support
Option 1: Verify SharePoint and OneDrive sharing model
Step 1: Please ask your SharePoint or IT admin to confirm whether Entra B2B integration is enabled. They can run the following command in SharePoint Online Management Shell:
Connect-SPOService -Url https://<tenant>-admin.sharepoint.com
Get-SPOTenant | Select EnableAzureADB2BIntegration
If the result shows True, the integration is enabled. If False, it is not yet enabled.
Step 2: If the external user does not yet exist in Entra ID, ask the file owner to reshare the file or site. It is important to generate a new sharing link rather than reusing the existing one.
Step 3: Ask the external user to open the new link and complete sign in. A guest account should be created automatically during this process.
Option 2: Review Entra External Collaboration settings
These settings often block guest creation even when SharePoint sharing is correctly configured.
Step 1: Go to Microsoft Entra admin center > Entra ID > External Identities > External collaboration settings.
Step 2: Review Guest invite settings:
The admin may consider setting it to "Anyone in the organization can invite guest users".
If it is restricted, the admin may need to adjust the setting or assign appropriate permissions.
Step 3: Review the Collaboration restrictions section and confirm that the external user’s domain is not blocked.
Step 4: Save any changes after updating the configuration.
Option 3: Manually create the guest user (workaround)
This can help restore access quickly while further investigation continues.
Step 1: Go to Microsoft Entra admin center, then navigate to Entra ID, Users > Select New user > Invite external user.
Step 2: Enter the external email address and display name, then send the invitation. Confirm that the user appears in the list with status Pending acceptance.
Step 3: Ask the file owner to reshare the file or site after the guest user is created.
Step 4: Ask the external user to accept the invitation, clear their browser cache by selecting All time and then sign in using the same email address that received the invitation.
Note: If the external user signs in with a different account, access may fail and require deleting and reinviting the guest user.
Option 4: Contact Microsoft Support
If the issue still persists after trying the steps above, I recommend reaching out to your IT administrator to create a support ticket via Microsoft 365 Admin Center > Support > Help & Support for further backend investigation.
A technical support engineer can perform a remote session to investigate the situation, verify the backend configurations, and run any necessary synchronization tools to resolve the problem. If the issue requires further attention, they can escalate it to a specialized team for deeper analysis.
I hope this information is helpful. If you have any questions or need further support, please don’t hesitate to reach out at any time.
Thank you for your patience and understanding.
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have any extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.