To export messages from Archive Manager you can use the Search Exporter tool.
You need to install the tool on a workstation with a 32 bit version of Outlook 2007,2010 or 2013, 2016 installed
- From the Archive Manager Web Interface open the Archive Manager Administration Website.
- On the left hand side Look for Download Tools and click on it.
- In the right hand pane the Archive Manager Search Exporter tool should be at the top of the list.
- On the far right under Download click on the Search Exporter link to download the tool.
- Once Installed add the mailbox you want to export to your standard mailboxes then on the search page select the Mailbox tab
- Click the dropdown to the right of Mailbox: and select the mailbox you want to export and click search.
- Then to the far right of the search button click Export | Open with will open Search Exporter
- Choose your Export directory and select PST as the type.