I got this script from roblox developer website :
local StarterGui = game:GetService("StarterGui") StarterGui:SetCoreGuiEnabled(Enum.CoreGuiType.Backpack, false)
It works on a baseplate, but on my game dont works, can someone help me?
First make a local script, and put it inside StarterGui, then type this in
game:GetService('StarterGui'):SetCoreGuiEnabled('Backpack', false)
Disabling a backpack server-sided is bad practice. It's cleaner and best to use local scripts when doing things like disabling backpack, leaderboard, ect.