Microsoft Office Tutorials and References
In Depth Information
actions that modify or delete email content. This is by design because mailbox operations
should continue to function normally. This is a very significant Microsoft strategy because it
balances your organization’s compliance requirements and at the same time does not affect
the productivity of your users. When email content is on hold, it is discoverable.
A Legal Hold in Exchange Online 2010 is applied at the mailbox level and implemented through
the EMC, ECP, or Windows PowerShell. While the concept of immutability can be accomplished
through Legal Hold, the ability to apply it only at the mailbox level might not be granular
enough because too much content might be placed on hold. Nonetheless, what is important is
that content is immutably preserved and, with a large personal archive, the space consumption
as a result of content preservation under Legal Hold is not an issue.
In Exchange Online 2013, Legal Hold is renamed In-Place Hold, and it now addresses the ability
for you to be more granular in selecting the content to preserve by introducing two types of
● Time-based hold, including indefinite hold
● Criteria-based hold
Time-based holds, sometimes referred to as rolling holds, work like an MRM retention tag
in that the hold is applied based on the timestamp of an email. As long as the timestamp of
the email falls within the limits of the time-based hold, the email content will be preserved
and is discoverable through a multi-mailbox eDiscovery search. After the timestamp of the
email falls outside the time-based holds, the content of the email will no longer be
preserved and will be subject to the modification or deletion actions of the user or MRM.
Criteria-based hold relies on keywords and Boolean logic to preserve content. Aside from a
keyword criteria match, you can also specify source and recipients, date ranges, and
message types (email, calendar items, and so on).