I bought a new laptop(dell inspiron), window 8 came preloaded in it . when I ran the set up of microsoft office 2007, it was asking product key but I skip that but whenever i open microsoft word message comes for product key and there was the warning that I can only open it for 25 times. what is it and how i'm I supposed to find product key to stop these messages.
Your laptop probably came with a trial version of Microsoft Office. It generally expires in 30 days or so. You need to purchase a valid license for Microsoft Office if you wish to continue using it without those annoying messages.
Alternatively, you can use a free office program, such as Open Office which is about 95-99% compatible with Microsoft Office.