Is Kerio 2.1.5 an efficient firewall?
Myth
Kerio 2.1.5 is used by many as a decent firewall and is thought to be very useful to protect the computer from any harms coming from the Internet.
Truth
Kerio 2.1.5 has been a very good firewall that has been developed by its creators but has several flaws within its conception. Hence, it has been enhanced to give better results. I will hence suggest you to use the upgraded versions of this software and to avoid using the version 2.1.5