Exported PST is empty when exporting a not cached folder in Outlook

Question

Hi,

I tried to export a PST file from a users mailbox folder that he can import the PST file again in his online archive.

After the export the PST file is only 265kb big and empty.

The folder is not cached in Outlook:
* Serverfolder contains: 6 items
* Offline folder contains: 0 items

When I try it with a cached folder the PST File is not empty.

The users mailbox is 50GB therefore I can not cache all of his files.

Are only the cached files exported to a PST file?
Is there a possibility for exporting all files of the folder without caching all items of the folder?
Or can you download/cache a single folder without caching the entire mailbox?

Thanks

Answer 1

Exporting only exports the cached content and not what is only available online.

Caching applies to the entire mailbox. However, you can set sync filters at folder level (Right click folder-> Properties-> Synchronization-> button Filter...) to reduce the amount of data that gets synced for that folder.

Caching a 50GB mailbox into an ost-file is possible and will leave you most likely with an ost-file smaller than 50GB as some parts will be stored in a compressed way within the ost-file.

However, instead of doing this client-side, consider using Retention Policies and/or Retention Tags so the items will be moved automatically within the service.
See: Retention tags and retention policies in Exchange Online

Answer 2

Here's what worked for me.

Keep the empty PST file export (or create one).

Open it in Outlook.

Go to the folder in the mailbox you want to export.

Click the "Click here to view more on Microsoft Exchange" to show all the non-cached messages.

Note the count of "Items:" in the lower left.

Select All

Right click > Move > Other Folder... (remember, this is a MOVE)

Navigate to the PST you opened and click OK.

All items will move. Be patient and leave your PC alone until it finishes.

Double check the "Items:" count to ensure all items moved. If the process gets interrupted, you will have to start again.