Office 2007 OEM (Original Equipment Manufacturer)/ Retail Version

Your computer was pre-installed with a version of Microsoft Office 2007. Should you ever need to reinstall your version of Office, the fastest and easiest way is via a backup copy. You can obtain a backup copy now.

http://www.microsoft.com/office/backup2007/en-us/default.mspx

Office 2010 PKC (Product Key Card – previously called OEM)/ FPP  (Fully Packaged Product previously called Retail) Version

If you need to reinstall your preloaded Microsoft Office 2010 software, you can do so from this site. To download or order a backup DVD you will be required to provide a valid Office 2010 Product Key.

http://office.microsoft.com/en-us/products/microsoft-office-2010-backup-FX101853122.aspx?CTT=5&origin=HA101847520