Single user can not authenticate using Outlook 2010(desktop) or Outlook 2003(various thin-clients) or through webmail to an Exchange 2007 server. I have deleted the mail profile and added it back. I have given myself access to her mailbox and tried accessing through webmail. I have checked her mail settings against other users settings. Nothing seems to work. What other info should I look for to help solve this issue? It seems to me her mailbox is broken on the exchange server and nothing is wrong with her client but I'm not an exchange guru.