I shared a SharePoint site with external users, and access worked initially. After one guest user started having problems, I deleted their account from Entra ID and recreated it with the same sign-in address. The recreated account can access newly created SharePoint sites, but it cannot access the original site or even individual files shared from it. The user always receives a "You need access" message, regardless of whether the account has been explicitly approved or added to the site permissions. I also cannot find any obvious reference to the old account in the visible permissions. What could be preventing access to this one site?
3 Answers
The underlying issue is usually the changed object ID rather than a sign-in failure, so sign-in logs may not reveal much. New sites work because they do not contain the old cached identity, while the existing site continues resolving the invitation to the deleted account.
The site probably still has a stale record in its hidden User Information List. Even if the guest is not shown in a permission group, the old object ID may still be associated with that email address. Check the site's user information page for the guest and remove the old entry. You can also use the appropriate SharePoint Online PowerShell commands to remove the stale site user and external user, wait for the changes to propagate, and then share the site again. It is also worth checking whether the old guest remains in Entra's deleted objects and confirming that this site's external-sharing setting is not more restrictive than the tenant setting.
This can happen when a guest account is deleted and recreated instead of restored. The new account has a different Entra object ID, while the SharePoint site may still be holding the old ID. Microsoft has a Site User ID Mismatch utility that checks the site and guest address, detects the mismatch, and can remove the stale entry. After it removes the old identity, share the site again so SharePoint creates a mapping for the new account.
That fixed it. Removing the stale user entry and sharing the site again resolved the problem after it had been stuck for several weeks.