[grand.Theft.Otto]

I'm guessing you're using Grand Larceny (aka grandlarc, default Gamemode by the SA-MP team).

This gamemode doesn't allow miniguns, so if you ARE using it, look for

pawn Code:

public OnPlayerUpdate(playerid)

and remove all the weapons you don't want people to get kicked with, like the minigun line in the script:

pawn Code:

// Don't allow minigun
if(GetPlayerWeapon(playerid) == WEAPON_MINIGUN)
{
    Kick(playerid);
    return 0;
}