how did it know i used a nulled script
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A nulled script is a script that requires a license to legally use but the script has been illegally modified to remove the license protection implemented by the author of the script. Nulled scripts are illegal. As a general rule you should always obtain scripts and software directly from the author's website in order to avoid nulled scripts. Very often, nulled scripts also will have modified code inserted into them which will allow hackers to access your website or server, making nulled scripts not only illegal but very dangerous as well. VBulletin is a very popular high quality forum which is widely available in the form of a nulled script. VBuilletin is not a free script. It requires a paid license and be aware that VBulletin, (as well as the authors of other commercial scripts), have effective means of tracking down and identifying nulled versions of their scripts.
If you have any doubt about a script ask some questions before downloading or using it.
Always obtain your scripts and programs directly from the authors website and read the terms before downloading or using it.
