
Hi @Alex Lombardo ,
There are many reasons for this, let's do some checks:
- Check if the subcontractors have changed their email addresses or domains recently. If they have, you may need to re-invite them to your SharePoint site using their new email addresses or domains.
- Check if the subcontractors have accepted the invitation to your SharePoint site using the same email address or domain that they received the invitation at. If they have used a different email address or domain, they may not be able to access the site. You can ask them to use the same email address or domain that they received the invitation at, or you can re-invite them using the email address or domain that they want to use.
- Check if the subcontractors have access to other SharePoint sites in your company’s tenant. If they do, they may need to switch accounts when they try to access your SharePoint site. You can ask them to sign out of their current account and sign in with the account that has access to your SharePoint site.
- Check if there are any issues with the external sharing settings in your SharePoint site or your company’s tenant. You can verify that external sharing is enabled for your SharePoint site and that the subcontractors have the appropriate permissions to access the site. You can also check if there are any restrictions on the domains or email addresses that can be shared with. You can find more information on how to manage external sharing in SharePoint Online in this article.
Hope it is helpful.
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