Why do I have two OST files?

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Outlook version
Email Account
Exchange Server
I was looking into the possibilities of getting my Personal folders (PST file) onto a networked server so I can access those saved emails from a different computer. One web site mentioned using OST files instead. Okay - I can look into that.

First order of business is to *find* my OST, if I have one. And I see in AppData>>Local>>Microsoft>>Outlook that I have ~two~ OST files - outlook.ost and outlook2.ost. The outlook.ost file was last updated at logon this morning and is about 326 MB. The outlook2.ost file looks like it updates about every minute and is over 1.3 GB!!

Can I safely assume the outlook2.ost is just a scratch pad, and periodically (maybe at log off??) is writes to the other ost and dumps itself?

An ost is used by exchange for offline mail storage, it's only accessible by the account that created it. Outlook2.ost is a probably an old ost or could belong to a different account.

You'll either need to save the pst file to a network (not recommended, but many people do it) or move the mail back into your mailbox and open the mailbox on other computers.

If you move the pst, you need to make sure outlook is closed on the other computers - only one outlook can access a pst at a time.
Thank you, Diane, for the clarifications. I won't bother with the ost files, then.

You'd think that, as often as this has come up, the Outlook team would have integrated some kind of solution for this. Email is moved into the pst to get it off the exchange server. Keeping a chunk of years-old I'll-need-that-someday mails takes some space; multiply that by hundreds or thousands of employees and it's a big deal!

If the pst file is only me, and I'm only on one computer at a time, is it that much of a potential problem to network the pst file? I do know that it's likely at least one of the computers (my main desktop) will still have Outlook running when I go to another location and fire up a laptop or other machine to see my email.

Outlook puts a lock on the pst when it's opened, so yes, it can prevent you from opening it on the other computer. Do you need the old mail that is in the pst from the other computers? If it's not something you usually need to access a lot, only open the pst in the other computers when you need some thing in it.
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