The screen shows the vault stores listed in the Vault Directory that you chose.

You must choose the vault store that contains the destination archives for the PST files you are going to migrate. You are restricted to a single vault store for each run of PST Migrator. If you want to migrate PST files to archives in more than one vault store, you must run PST Migrator again.

When you start the migration process, the archive is locked (the Administration Console shows a status of 'Unavailable'), which prevents normal archiving to the archives in the vault store. If any attempt to archive to the archive is made, the item is turned back to a normal item and no event is logged.

Click the vault store you want to use, and then click Next to continue.