The “All People” view is a very convenient way of listing out all the users having access to the SharePoint site.
When a user navigates to the “People and Groups” section in a SharePoint 2007 site, a link called “All People” is available on the left hand navigation. Clicking on this link brings up a view of all the users across all the groups in the site.
But this “All People” view is hidden in SharePoint 2010 and the link is also missing in the “People and Groups” section. However one can still navigate to this view in a SharePoint 2010 by following the below mentioned steps :
Navigate to the “People and Groups” section.
Click on any of the groups.
Locate the “MembershipGroupId” query string parameter from Url in the address bar
Replace the value in the “MembershipGroupId” query string parameter with 0.
Reload the page and it will populate the “All People” View.