[Okta Webinar] Learn how to a build a cloud-first strategyRegister Now

  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 241
  • Last Modified:

Outlook 2013 better at cleaning up PST/OST Database?


I have several clients that have large Outlook 2010 Exchange databases. One in question is about 39GBs. However, when checking on properties and folder size, the local and server folder size is actually only about 24GBs.

Per Microsoft's documentation, Outlook is mean to autocompact itself when the computer is idle and will only leave about 5% of "white space" for performance reasons in the Outlook Database.

Doesn't look like its doing it, maybe its because the database is too big and to compact something like that on a regular basis to clean it up would be a very time intensive job.

Or Outlook doesn't think the computer is ever "idle". I guess the question is, what is "idle" in this case? Could an online backup in the background think that its not "idle"?

Does anyone know if Outlook 2013 does a better job at keeping down the size of the Outlook Database? I noticed the other day when I set the slider for one user from keeping 1 year to 6 months of cached data it immediately reduced the database (.OST) by a large chunk, immediately cleaning up space. I'm wondering if this is also the case for the continued maintenance of the database or not. Any insight would be helpful.

1 Solution
John HurstBusiness Consultant (Owner)Commented:
I have Outlook 2010 on my Windows 7 machine and Outlook 2013 on my Windows 8 machine. I file my email and clear out my Inbox every Saturday Morning. I compact both PST files and they both take the same amount of time to compact.

Both systems archive every 2 months and when that happens, I compact again. Outlook 2010 always takes longer to compact after archiving than Outlook 2013.

So Outlook 2013 may be a bit more efficient at maintaining a PST file but it has not eliminated the need to do some manual and regular maintenance.
Seth SimmonsSr. Systems AdministratorCommented:
you're talking about 2 different technologies here
outlook is the client while exchange is the server
what do you mean by 'outlook exchange database'?  what is 39gb?

the fact that the server and local (cached, ost) size is about the same indicates there is little whitespace
i've never seen outlook (prior to 2013) automatically compact an ost file in the background but have seen it for a pst file
David Johnson, CD, MVPOwnerCommented:
The database file on the server will not be compacted by the client, the client can only compact the .ost local file.
Has Powershell sent you back into the Stone Age?

If managing Active Directory using Windows Powershell® is making you feel like you stepped back in time, you are not alone.  For nearly 20 years, AD admins around the world have used one tool for day-to-day AD management: Hyena. Discover why.

RFVDBAuthor Commented:
I'm talking about the local .OST on the client workstation. The actual .OST is about 39GBs however in Outlook when you find out the folder size, its about 25GBs.

In this article it states that Outlook will automatically compact your Outlook database:
John HurstBusiness Consultant (Owner)Commented:
Any insight would be helpful.  <-- I have both Outlook 2013 and 2010 on different computers and operating systems as noted above. By and large I must compact manually. It does not happen by itself.
Seth SimmonsSr. Systems AdministratorCommented:
then follow the steps in that article to compact the ost manually and you'll recover nearly 14gb of disk space
it can do it automatically but is conditional
John HurstBusiness Consultant (Owner)Commented:
@RFVDB  - Thank you and I was happy to help.

Featured Post

Simplify Active Directory Administration

Administration of Active Directory does not have to be hard.  Too often what should be a simple task is made more difficult than it needs to be.The solution?  Hyena from SystemTools Software.  With ease-of-use as well as powerful importing and bulk updating capabilities.

Tackle projects and never again get stuck behind a technical roadblock.
Join Now