Outlook 2010 stores all the mails, calendar items, contacts and other information in PST format and you can directly take a copy of this PST file whenever you need a copy of emails. Backup my mail is an useful freeware app for Windows which can automatically backup your Outlook emails (PST file) to the desired location. You can schedule the backup process and it will take a copy of the PST file based on the schedule.
In the main screen you need to specify the backup folder and also specify the user permission in case you need to run as a different user. The schedule tab allows you to schedule a backup process.
You can specify the start date and time and also repeat the process every specified number of days. Backup my mail is a simple GUI for console program hobocopy and this tool copies all pst file from default profile Microsoft Outlook mail client to backup folder. You can opt to delete the old PST files once the new files are backed up. This can be done from the options.
Overall Backup My Mail is nice tool to automatically backup Outlook PST files.