A group of Microsoft Products and technologies used for sharing and managing content, knowledge, and applications.
Dear User,
Good day!!
Apologies for the inconvenience caused and please don’t worry, let’s work together on your concern and move towards a resolution path.
I understand your concern and to my knowledge, I would like to confirm whether the external user is able to access the shared content via InPrivate or Incognito window of the browser:
Open the Google Chrome> Click on the three new dots at the top right> New Incognito window> Access the shared content.
If the same problem happens, please follow the below steps and check the outcome:
- Open the SharePoint Online site where the external user is having the problem> Settings> Site Permissions> Advanced Permission Settings.
- Open the Site Name – Members Group> In the end of the URL, change 5 to 0> Click Enter.
- In the People and Groups page, select the external user with the problem> Actions> Delete this user from the site collection.
- Wait for some time and re-add the external user to the site to check the outcome.
If the same problem persists, I believe the problem should be further investigated by related development team via collecting HAR logs because there is no any related service incident reported at the Microsoft Service Health dashboard.
I do feel regret for not resolving the problem and redirecting you to the related development team but the fix to your concern can be find out through the HAR logs and suggest you raise a support ticket from the Office 365 admin center, where the related team will investigate the problem further by collecting the HAR logs.
Reference: Get support - Microsoft 365 admin | Microsoft Learn
Note: To create a support ticket, you need to have admin privileges and if you aren’t admin of your Office 365 organization, please contact the admin of creating a new ticket
Appreciate your patience and understanding. Have a great day!!
Best Regards,
Sophia