Problem with file ownership

So I am running a forums on your host center and I went to install a addon for it known as “cometchat” and when I went to run the install file I get the 403 error Forbidden

You don’t have permission to access /cometchat/install.php on this server. So I cant install it can I have some info as to how i fix it I tried setting permissions on it to 777 and that didnt help either so I cant install this I am currently running Xenforo for the forums

Chat scripts are not allowed on our hosting, which is why your chat script is probably blocked.

Well I am sorry I feel stupid I will pay for premium now.