i have a powerpoint project due tomorrow. i have the microsoft powerpoint 2007 but when i click on it, it says that:

enter your product key
type your 25-character product key
althought you are not required to enter your prodect key now, we recommend you do so for ease of validating your microsoft office license.

what do i do? i dont know the product key! please help im not good at computers! im freaking out right now!
i dont even know what a product key is!
i did not buy it, it came with my computer.