How can I access a player's body part in a server script?

[TransDevv (transportdeveloper3)]

I have a localscript that basically attaches a gun to the player’s right hand via a motor6d and it all works beautifully in a localscript but when I decided to do the same process for the server replication it all just stopped working and sadly this is not the first time I get stuck on the server side.
Here is the code: (explanation below the code)

local function ReplicateGun(player: Player, state: string, gun: string)
	if state == "Create" then
		print(gun)
		local thirdPersonJoint = Instance.new("Motor6D")
		local ThirdPersongunModel = replicatedStorage.Items:FindFirstChild(gun):Clone()
		local ThirdPersongunName = gun.Name
		local rightHand = player.Character:WaitForChild("RightHand")
		thirdPersonJoint.Name = "ServerMotor6D"
		ThirdPersongunModel.Parent = rightHand
		thirdPersonJoint.Parent = rightHand
		thirdPersonJoint.Part0 = rightHand
		thirdPersonJoint.Part1 = ThirdPersongunModel:FindFirstChild("ImportantParts"):FindFirstChild("Handle")
		thirdPersonJoint.C0 = CFrame.new(0,0,0) * CFrame.Angles(math.rad(0),math.rad(90),math.rad(-90))
	else
		local thirdpersonGunModel = player.Character:WaitForChild("RightHand")[gun] -- error here
		player.Character:WaitForChild("RightHand"):FindFirstChild("ServerMotor6D"):Destroy()
		thirdpersonGunModel:Destroy()
	end
end

caster.LengthChanged:Connect(onLengthChanged)
caster.RayHit:Connect(onBulletHit)

GetInfoRemote.OnServerEvent:Connect(GetGunInfoFunc)
ReplicateGunRemote.OnServerEvent:Connect(ReplicateGun())

sorry for the code being hard to read, I’m really sorry

basically the code is supposed to create a motor6d, parent the M6D and the gun model to the hand, then adjust the C0 and C1 stuff later down the road. The main error while testing starts at the line after the else statement (local thirdpersonGunModel), it reads attempt to index nil with character. I already tried countless other methods like adding a playerAdded function at the start of the code but it also didn’t work.

I don’t have any other ideas, if anyone knows how to overcome this issue then I would be super grateful, even if not then I’m still super grateful
thank you

[FrankenCoder]

Maybe try something like:

	else
		if player.Character then
			local RightHand = player.Character:WaitForChild("RightHand")
			local thirdpersonGunModel = RightHand:WaitForChild(gun)
			RightHand:FindFirstChild("ServerMotor6D"):Destroy()
			thirdpersonGunModel:Destroy()
		end
	end

[jaymeyzy (jaymey)]

local function ReplicateGun(char, state: string, gun: string)
	if state == "Create" then
		print(gun)
		local thirdPersonJoint = Instance.new("Motor6D")
		local ThirdPersongunModel = replicatedStorage.Items:FindFirstChild(gun):Clone()
		local ThirdPersongunName = gun.Name
		local rightHand = char:WaitForChild("RightHand")
		thirdPersonJoint.Name = "ServerMotor6D"
		ThirdPersongunModel.Parent = rightHand
		thirdPersonJoint.Parent = rightHand
		thirdPersonJoint.Part0 = rightHand
		thirdPersonJoint.Part1 = ThirdPersongunModel:FindFirstChild("ImportantParts"):FindFirstChild("Handle")
		thirdPersonJoint.C0 = CFrame.new(0,0,0) * CFrame.Angles(math.rad(0),math.rad(90),math.rad(-90))
	else
		local thirdpersonGunModel = char:WaitForChild("RightHand")[gun] -- error here
		char:WaitForChild("RightHand"):FindFirstChild("ServerMotor6D"):Destroy()
		thirdpersonGunModel:Destroy()
	end
end

game.Players.PlayerAdded:Connect(function(plr)
	plr.CharacterAdded:Connect(function(char)
		ReplicateGun(char...)
	end)
end)

this will make the function run every time a players character is loading in, but you need to add the other params to the ReplicateGun call in the character added event

[TransDevv (transportdeveloper3)]

Sorry for the late reply, but it worked! Thank you!
I kind of tweaked it a bit because for me if I connected the function outside of the remoteEvent then it wouldn’t work, so I instead created a direct function inside of the remoteEvent. Here is the code for anyone who might have the same problem:

game.Players.PlayerAdded:Connect(function(plr)
	plr.CharacterAdded:Connect(function(char)
		ReplicateGunRemote.OnServerEvent:Connect(function(plr, state: string, gun: string)
			if state == "Create" then
				print(gun)
				local thirdPersonJoint = Instance.new("Motor6D")
				local ThirdPersongunModel = replicatedStorage.Items:FindFirstChild(gun):Clone()
				local ThirdPersongunName = gun
				local rightHand = char:WaitForChild("RightHand")
				thirdPersonJoint.Name = "ServerMotor6D"
				ThirdPersongunModel.Parent = rightHand
				thirdPersonJoint.Parent = rightHand
				thirdPersonJoint.Part0 = rightHand
				thirdPersonJoint.Part1 = ThirdPersongunModel:FindFirstChild("ImportantParts"):FindFirstChild("Handle")
				thirdPersonJoint.C0 = CFrame.new(0,0,0) * CFrame.Angles(math.rad(0),math.rad(90),math.rad(-90))
			else
				print("destroyed gun on server")
				local thirdpersonGunModel = char:WaitForChild("RightHand")[gun] -- error here
				char:WaitForChild("RightHand"):FindFirstChild("ServerMotor6D"):Destroy()
				thirdpersonGunModel:Destroy()
			end
		end)
	end)
end)