If you have authenticated the SharePoint in the PortalXpand, you can manage the Documents sharing rights for the Portal Users of the customer portal.
From here, you can enable “Document Access” and allow to add the Files & Folders to the portal users from the Customer portal. You can enable the ‘Delete’ option if you want to give permission for the delete.
After configuring the Role details, save the details and the newly added portal user role will be listed under the Roles.
Note: If admin has enabled the entity for the SharePoint from the Dynamics 365, only then it will be listed under the Document section.
From the list of the Portal user roles, you can change a role to the users (contacts) that were already assigned and can replace with another role as you want to assign.
By clicking on the Replace Role option, a pop up will appear to select another role from the drop down list.
Once you select another role, it will replace the current one and assign the new role to all the contacts (portal users).
Note: Here in the drop down list, only those Roles will appear whose Relation Type is common.