The Clean Limited Access tool eliminates unused Limited Access permission levels that no longer relate to existing permissions on-site elements.
The Limited Access permission level is assigned automatically when you provide access to one specific item in a site or subsite with broken inheritance. If the permissions on the particular item are removed, the Limited Access permission level granted previously remains but is no longer required.
Find out more about SharePoint and the Limited Access permission level here.
Prerequisite(s)
You have site collection admin permissions on your targeted site collection(s).
Note: Site collection admin permissions are required even if you have higher admin privileges like SharePoint admin or Global admin permissions. For more information, see Microsoft administrative permissions.
Tip: To manage all your site collections, you can connect to your central admin or admin center with SharePoint admin, Farm admin, or Global admin permissions.
How-To
Select your items on the Explore screen.
Click Clean Limited Access in the quick actions menu.
Click Clean Now (you can Schedule this action as well).
The task will now run.
In the case that there are warnings or errors, they will be displayed with details in separate tabs near Results.