Weapon wont fire

So i downloaded a few SWEPS and 5 of them wont fire when I press the main fire button, but the secondary still works, for example: a M4A1 with a grenade luancher. So does anyone know whats doing this and how it can be fixed?

Humm… is it only one swep or all?

well i downloaded a pack and 3 of five wont work and then i downloaded another one wich also dosent work

You should really ask whoever made the pack, or at least tell us what pack it is, as it’s got to be a problem with the lua.