Keeping Computer Secure

Recently I have to reinstall my Windows package. During this year I have to do it twice. It is very annoying. When I reinstall the operating system in my computer, automatically I have to reset the configuration of certain system to get my personalization.
When I talk to some computer technicians, why does my computer often get some error operation, I get one fixed answer. My computer is not protected well, there is not an Antivirus Software working inside my computer. That is why dangerous virus easily intrudes into my computer and destroys some important file systems. Then my computer can not run properly.
The technician suggested me to find the Best Anti Virus Protection. It will protect my computer from intruder. The virus protection software will watch every activity inside my computer. If it detects certain unknown file or program it will let me know. The best is the virus protection will recommend the action to take.
The advice is logical. Finally I got the Antivirus Software Download and set up it. Now I do not get trouble and error operation any more. My computer is running well and working securely. I like my computer.