Today we found such a strange error with one of the servers, and it was preventing us from accessing its cPanel. Though someone has intentionally did it to prevent server from renewing the certificate automatically, I thought to share this as someone may meet this error with some crazy servers 🙂 . So the file in error is /var/cpanel/template_compiles/usr/local/cpanel/base/unprotected/lisc/licenseerror_whm.tmpl and you should check its permission and attributes to make sure it is writable. In our case, it had immutable attribute set. Removing the attribute fixed it.