We can enable auto approval in SharePoint community site to
get access automatically without request approval. We can enable the auto
approval for only community site; it will not apply membership for any group.
Generally auto approval is suitable for open communities without having
restrictions. So whenever we want to configure
auto approval, we have to manage the permissions. If we have auto approval in SharePoint
community site, whenever new user clicks on Join button, we can get an email.
We can manage the permissions of the user in People and Groups settings on Site
settings page
To enable auto approval, Click on Community Settings link
Community site home page, Community tools WebPart.
We can see “Enable auto-approval” check box (We can see this
option only for root site collections. This will not be available for sub sites)
Click on ok to save the settings.