2 Addons folders ....

[The Neurocyber]

Ok, i may look stupid to ask that but what the difference between OFP\Addons and Rez\Addons folders?

Now two "addons" folders but where the hell should i put new addons?...unofficial i mean...

[Skaven]

There are no stupid questions mate.  
Technicaly, you should place all addons made for Pre- Resistance in the OFP\Addons, all addons made for 1.75 Resistance (or above)  should be placed in the Res\Addons.
However it doesn't mean that if you don't do that exactey that it won't work, but I would reccomend you to do it this way  

[Eviscerator]

the only reason there is a res/addons is because if you install 1.00 and then res>1.85>190>1.91 you dont have a ofp/addons, so it allows you to have addons, although if you want to use 1.00-1.46 and you install some of the upgrades/gold you will have to use the ofp/addons as some of the addons in the res/addons folder will need resistance to play, they will cause errors if they were in ofp/addons, if you dont use non-res ofp its probably easiest to put everything in res/addons