So how can you tell the difference between a nulled version of a forum software to a retail version?? Besides that a full version is bought.

Is there a way to check the script, coding, etc??

The reason is because I found a site that provides link to BOTH a retail AND nulled version of a forum software...I would really like to download but don't want to download a nulled version.....so help??

Usually there is a way to tell. Why don't you purchase the forum software from the actual vendor? No chance of getting a cracked script there. Or use a free open source alternative like Vanilla.

well nulled versions usually have something changed or some features disabled.

for example VBulletin has quick post disabled or in IPB you can find in a file (i will not say which one) a line that says

client_null 0; (this means its retail)

if you want a retail version for free i suggest you talk with friend that has that forum and convince him/her to lend it to you or at least split the fee that you have to pay for it.

One big difference that we shall all point out is that with NULLED you can get banned. With a legal one you often get free upgrades from the provider.