If you are running an Exchange server and you need to manage users' mailboxes or need to run backups you will want to have full access to the users' mailboxes. In Exchange 5 or earlier you did this with the option "Show permissions page on all objects". In Exchange 2000 and 2003 the easiest way to do this is as follows:
1. Open regedit
2. Browse to HKCU\Software\Microsoft\Exchange\ExAdmin
3. Add Add a "ShowSecurityPage" DWORD value with a value of 1 to
Now you can remove the deny permissions on the organisation for the administrator, domain admins and exchange admins.