SharePoint 2007 中彻底删除用户操作如下:
Site Actions—Site Settings—User and Permission—All people，然后选中这个用户，选择Action—Delete Users From Site Colletion.
但是SharePoint 2010 取消了这个功能,但依然保留了该功能页面,需要手动输入地址: /_layouts/people.aspx?MembershipGroupId=0
原文: "SharePoint 2010 中如何彻底删除用户" http://blogs.technet.com/b/msbluehat/archive/2010/08/10/sharepoint-2010.aspx