If the Base URL is incorrect, CometChat will stop working on your site.
If you are using CometChat over a cross domain or sub domain then the Base URL detection algorithm may fail to detect your site’s base URL. Therefore in this case you will have to put the Base URL manually.
For example, if www.chatyoursite.com is your main domain and CometChat is installed at alternate domain i.e. www.chatyoursite.com, in this case your base URL will be http://www.chatyoursite.com.
In most cases, your Base URL will be ‘/cometchat/’.