The reliability is excellent. It will not allow you to do anything with your pc unless it has been updated or restarted for some reason. This software was easy enough to use even if i am new to computers. There are several other softwares that can be used instead such as Avira but this one gave me more features than others I had tried before. Sometimes when my computer restarts it takes longer then usual to start up again after having windows update installed. If you have problems updating your antivirus program make sure you take screenshots of everything so it makes troubleshooting much easier later on. My problem solved!