Getting Errors

I’m getting the following errors in the code:
(14,25): error CS1502: best overloaded method match for ‘UnityEngine.MonoBehaviour.StartCoroutine(System.Collections.IEnumerator)’ has some invalid arguments

(14,25): error CS1503 Argument ‘#1’ cannot convert ‘void’ expression to type ‘System.Collections.IEnumerator’

Here is the code:

using UnityEngine;
using System.Collections;

public class MyWeapon : MonoBehaviour {

	public float Damage = 100f;
	public float MaxDistance = 100f;
	private float Distance;
	bool isFiring = false;
	public void Update() {
		// ...
		if (Input.GetButton("Fire1") && !isFiring) {
		// ...

	public void Shoot() {
		RaycastHit hit;

		Ray ray = Camera.main.ViewportPointToRay(new Vector3(0.5f,0.5f,0f));
		if (Physics.Raycast (ray, out hit, 100f)) {
			{ Distance = hit.distance;
				if (Distance < MaxDistance)


	IEnumerator COFire() {
		isFiring = true;
		yield return 0;
		yield return new WaitForSeconds(5f);
		isFiring = false;


I know its probably a really simple answer but I havent been able to find a match, especially in C#

I’m complete beginner noob level

Shoot() should return an IEnumerator.

See docs.