The popularity of Microsoft Office unchallengeable. Microsoft Office Outlook is widely used for email access, for planning a day-to-day schedule, managing contacts or administering one's affairs. That is the same for business and home. Password protection is initially present in Microsoft Office applications. Microsoft Office Outlook is not an exception: you can set a password to protect your email accounts (a mailbox password) or restrict access to your personal folders (a pst password).
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Windows Server 2008