OST to PST Outlook export question I've always wondered..

thecomputerguy

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Hopefully this is simple.

In the past when I exported an exchange account to PST (like if someone is retiring, or wants a set of data for legal purposes sent to a lawyer in PST format), I felt like I had challenges in the past due to the sync days i.e. 3 months, 6 months, 1 year etc.

I can't really explain the challenges I had but this lead me to what I'd do below.

I'd turn off cached exchange mode and export the PST while directly connected to the Exchange server to make sure all mail was available in Outlook.

Once done I'd turn cached exchange mode back on and move on.

Is this necessary? If you export to PST with say 3 months of cached exchange mode turned on in let's say a fresh profile that really only has 3 months of data in it, does the export tool know enough to grab all that stuff beyond 3 months as well?

What about (THE DREADED) imap account?
 
I've always slid the bar to the right to "download all" as part of our default setup anyways...but if I had to export the mailbox....I go in and double check to make sure the bar is all the way to the right so it's downloaded "all" email. That's just part of how we've set up clients for 30+ years.

Per Microsofts instructions, they also say to slide the bar to the right.

If you sit down at a computer with an old mailbox..and Outlook was only set to 1 year default on the slide bar, if you go slide the bar to the right...it could take more time than you have to wait....for Outlook to cache all the email locally before you go export.....Outlook could be busy downloading/syncing for quite a while.
 
I've always slid the bar to the right to "download all" as part of our default setup anyways...but if I had to export the mailbox....I go in and double check to make sure the bar is all the way to the right so it's downloaded "all" email. That's just part of how we've set up clients for 30+ years.

Per Microsofts instructions, they also say to slide the bar to the right.

If you sit down at a computer with an old mailbox..and Outlook was only set to 1 year default on the slide bar, if you go slide the bar to the right...it could take more time than you have to wait....for Outlook to cache all the email locally before you go export.....Outlook could be busy downloading/syncing for quite a while.

Ah ok ..


So it sounds like the way I'm doing it isn't necessarily wrong but I risk severing the connection for any reason at any point and then having to acknowledge that and restart the export with "do not export duplicates checked."

The only issue I see with the M$ approved method by sliding the bar all the way to the right is possibly leaving a honker of an OST on the system in the event that the mailbox is 50+ GBs. Then possibly having to slide the bar back and delete to OST to re initiate a new download set with a manageable file size.

Also my method seems better in cases where you are only exporting a small selection of folders as opposed to the entire mailbox.

Sounds about right?
 
The OST has a 50GB limit, so as soon as you hit it Outlook stops working anyway. Exporting mailboxes >50GB in this way is a huge chore, which at that point it would be cheaper to license it for Datto SaaS backup, or DropSuite let the cloud backup that mailbox to the cloud, and export it from those tools.

Both tools can do GSuite as well as M365. Though I'm not certain to their ability to deal with IMAP.
 
What am I missing here, whether for IMAP or Exchange, isn't one of "the big points" of server-side protocols to offload long-term storage of not-frequently-accessed email to the server? You always have access, on demand, provided you haven't actually deleted your account.

For people who have ridiculously huge email archives it's a blessing for only a limited amount of relatively recent material to be stored locally. What's the driving force behind having it all that way? It defeats the design purpose, doesn't it?

You don't lose access to anything, ever, unless the account were to be deleted, and you can set it up on as many machines as you wish, and grab any given message that is not currently in local storage on-demand if you need it.
 
Ah ok ..


So it sounds like the way I'm doing it isn't necessarily wrong but I risk severing the connection for any reason at any point and then having to acknowledge that and restart the export with "do not export duplicates checked."

The only issue I see with the M$ approved method by sliding the bar all the way to the right is possibly leaving a honker of an OST on the system in the event that the mailbox is 50+ GBs. Then possibly having to slide the bar back and delete to OST to re initiate a new download set with a manageable file size.

Also my method seems better in cases where you are only exporting a small selection of folders as opposed to the entire mailbox.

Sounds about right?

50 gigs is only the default limit. You can edit the registry and crank that up to 100.
Granted...it's not a "best practice".
Naturally...yes..tiny hard drives without adequate space would fill up. Just like if it was someone downloading huge video files or something.

And...on low system spec rigs...(spindles, inadequate RAM, etc) Outlook runs sluggish as heck with huge OSTs. I have a few users where I have edited the registry and they regularly work with 60 or 70 gig OSTs...good hardware they're on, Outlook runs like a champ. Yes online archiving is the better approach...and I've shifted most large mailbox users to that.

Cherry picking subfolders...of course if that's all you need, just get those,...quicker than the whole mailbox.

Or export the mailbox to a PST from 365 online admin portal...skip the workstation.
 
What am I missing here, whether for IMAP or Exchange, isn't one of "the big points" of server-side protocols to offload long-term storage of not-frequently-accessed email to the server? You always have access, on demand, provided you haven't actually deleted your account.

For people who have ridiculously huge email archives it's a blessing for only a limited amount of relatively recent material to be stored locally. What's the driving force behind having it all that way? It defeats the design purpose, doesn't it?

You don't lose access to anything, ever, unless the account were to be deleted, and you can set it up on as many machines as you wish, and grab any given message that is not currently in local storage on-demand if you need it.

It's always for performance reasons or to resolve issues with search. If online-only worked just as fast I'd never consider caching locally. But unfortunately in my experience, and feedback from clients, it doesn't.
 
But unfortunately in my experience, and feedback from clients, it doesn't.

And I'm not going to question your experience. Mine has been different, but even my business clients seldom have need to hunt for years-old material, and are willing to wait a bit longer on those occasions where they do. This would drive one insane if you're constantly "going into the vault."

One of the reasons I've gotten clients that I can away from Outlook or any email client is it puts this whole issue to rest quickly. Any webmail interface to an IMAP or Exchange server is lightning fast, in my experience, provided the internet itself isn't constipated at the moment.
 
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