I bought a vBulletin license earlier on in the year and have paypal reciepts etc to prove it, I installed the 3.3.6 verison when I first bought the software and I recently upgraded to 3.6.8. I got an email the other day from someone saying that I am using a nulled script and they were going to report me, WTF is that all about? How do they know if you are using a nulled script and what can I do in order to check my forum is mine and someone is not tampered with it and stole my license, or is that even possible?