chmod: changing permissions of '/opt/lampp/htdocs': Operation not permitted code example
Example 1: chmod: changing permissions of '/opt/lampp': Operation not permitted
sudo chmod 777 /opt/lampp/htdocs
// lazy and risky fix
Example 2: chmod: changing permissions of '/opt/lampp': Operation not permitted
sudo chown –R [Username]:[Groupname] /opt/lampp/htdocs
// Better to change the owner than to allow everyone to access the file