I recently purchased Adobe Photoshop CS4 student / teacher version and I am trying to get the serial #. The program says to login to www.adobe.studentlicensing.com and enter the coupon code provided with the program. When I enter the code it says it is not valid. I previously had CS4 ( none student version) on my computer but the company it was licensed through closed so my program license expired. It was suggested that I remove all Adobe CS4 from my computer before loading the new one. Nothing works so far. I am not sure if I have removed all previous CS4 but I think so. I have called the seller of the new program and they cannot figure it out. Please can someone help. I am legitimately a student.