Multistreaming allows you to archive multiple mailboxes in parallel.
We recommend that you use five streams on each access node.
In the navigation pane, expand Solutions > Exchange Apps, and then click the Email Archiving App.
On the upper-right corner, click on Settings.
On the page that appears, in the General area, click Edit.
The General dialog box appears.
In the Max streams box, enter the number of streams that you want to use.
If you do not want to archive multiple mailboxes in parallel, enter a value of 1.