I purchased Adobe Photoshop CS4 extended from nikknak.com only to receive a pirated copy with an invalid serial number. I found out that the serial number was invalid by spending an hour on the phone with Adobe. I promptly notified the seller and expressed my dismay. I was told by the seller that he would give me a new serial number (which should have sent up a red flag). After waiting for days, I received nothing. I then requested a full refund, so I was told to return the copy. After returning the software, I waited for a response. After 5 days of waiting, the seller replied, "The software works perfectly and the serial number is valid." I then replied back to the seller that I just want a refund and I will be happy. Well, I guess I won't be getting one, so here I am. Stay far away from this seller! P.S. Paypal does not protect buyers whatsoever.