I get Invalid Product Key message when I try to install Office 2013 on my VAIO computer.
You get "Invalid Product Key" message when you try to install Microsoft Office 2013. It is because you have installed Office 365 on your VAIO computer. More information can be found at Microsoft website: http://office.microsoft.com/en-us/help/cant-go-from-office-365-to-office-2013-HA104050351.aspx?CTT=1
Before you install Microsoft Office 2013, the first thing you need to do is uninstall Office 365. For more information on the solution, refer to Microsoft Knowledgebase Article 2739501: http://support.microsoft.com/kb/2739501