I have a server running windows 2000 and Exchange 5.5 Standard edition with SP4. I have deleted users who are still occupying mailbox resources in the private information store. When I run exchange administrator and select mailbox resources the delete tab is grayed out. When I go into tools, the clean mailbox tab is grayed out. How do I delete these mail messages. I need to delete them before I run the defrag utility. I am getting close to the 16GB limit for my information store.