You can export entire mailboxes (smaller than 50GB) to PST, from the Exchange console:
New-MailboxExportRequest -Mailbox "Amy Smith" -FilePath "\\Server\Share\AmySmith.pst"
To get Status of the request:
Get-MailboxExportRequest | Get-MailboxExportRequestStatistics | fl
These should be output to a fast drive with plenty of capacity (not a shadow copy volume). When decommissioning a user account move the file to the company archive.
Begin by verifying the mailbox size:
Get-MailboxStatistics -server "post" | Sort @{expression=”database”;Ascending=$true},@{expression=”TotalItemSize”;Descending=$true} | select DisplayName,database,ItemCount,TotalItemSize
To enable these tools for the first time:
Add-PSSnapin Microsoft.Exchange.Management.PowerShell.E2010
New-RoleGroup -Name "Exchange Mailbox Import Export" -Roles "Mailbox Import Export" -Members "domain\admin" -DisplayName "Exchange Mailbox Import Export" -Description "This group handles permissions to the import and export commands in powershell."
New-RoleGroup -Name "Exchange Support and Diagnostics" -Roles "Support Diagnostics" -Members "domain\admin" -DisplayName "Exchange Support Diagnostics" -Description "This group handles permissions to the support diagnostics cmdlets in exchange."