Now that we have the technical reasons out of the way, let’s look at some more issues associated with PSTs:
I’ve been supporting Exchange messaging for over 10 years and observed many organizations amass an enormous data blob of PSTs. Sometimes humorously referred to as “Poor Storage Technology”, PST storage and support can represent a noticeable cost to most IT shops.
Organizations ranging from 2,500-10,000 users typically average 4-to-8 terabytes of PST data on the network at any given time, and I’ve seen some over 20 TBs. If I took an educated guess at what percentage of this data was A) relevant to the company business, and B) not stale (meaning past company retention policies) I would say only 20-30% is relevant and in-policy data.
I’ve worked with numerous customers ranging across all industry sectors (including Healthcare, Manufacturing, Oil and Gas, Government and University institutions to name a few) and there are 5 main approaches to dealing with PST infestation:
Ideally options #4 and 5 would be in every environment and mailboxes would never need to exceed 500MB. Unfortunately for many organizations, Enterprise Content Management (ECM) has not reached a level of maturity where users feel comfortable removing data from their mailbox and even though there is a system in place to manage their data they continue to use PSTs or their mailbox as a document repository.
Here is where Exchange 2010 archiving can step in and assist with managing this data in such a way that is familiar to both the end users as well as the administrators supporting the system. Take a look at the features of Exchange 2010 and compare the benefits from many angles. What are the support costs of a 3rd party solution such as additional SQL servers, separate provisioned storage on a SAN, licenses from third parties, high availability considerations are some examples. Take this information and compare it to what the TCO would be running the archive natively in Exchange 2010.
Start Here - Exchange 2010 Archiving, Retention, and Discovery.
*When researching Exchange 2010 documentation pay close attention to the document version as there have been several changes with the recent release of Service Pack 1.