SharePoint 2013/2016: Missing Access Request Settings
The following article describes two possible solutions when Access Request Settings are missing from Site Settings>Site Permissions.
Missing Outgoing Email Settings
When you navigate to the Site Settings > Site permissions and see the following view:
Verify Outgoing Email Settings in Central Administration:
Check out the following articles for possible configurations:
Inherited Permissions
(applies also to SharePoint Online)
The Access Request Setting is also missing when the site is inheriting permissions from its parent:
Stop inheriting permissions and the setting becomes available:
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