I have taken over the administration of an Exchange server. Each mailbox can be open by everyone else. I need all mailboxes to be secure and only accessible by that user.
If I go to "Active Directory Users and Computers" and select a user then click the properties of the mailbox > Exchange Advance > mailbox rights then I see the Everyone group as having read access. I cannot remove this group as I get the following error:
"You cannot remove "everyone" because the object is inheriting permissions from its parent. Turn off the options for inheriting permissions and try again."
Where do I go to turn off "inheriting permissions?".
Incidentally I have checked the Exchange Domain Servers group and the only members are XXXServ01 (the server name) which is in the Active Directory folder of XXXXXX.co.uk/domain controllers.