Our customer has a public web application where external users located in a trusted domain can log on to. External users should not be able to browse user information and we created a custom Web Application permission level to deny these permissions to certain AD...
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User Information ListRemove users from User Information List
This post describes how you can remove a user from the User Information List (UIL) in a site collection from SharePoint 2010 and 2013. SharePoint stores user information in the UIL to extract data when this user is being searched by the people picker. The people...