A very annoying and recurrent problem in most PCs is virus attack. Viruses come in many forms and get into the PC system in so many many ways. With most PCs nowadays connected to the Internet, viruses, worms, trojans, and many other forms of malwares can get through stealthily especially to an unsuspecting user. When a system gets infected, though it may have an antivirus software, the antivirus may no longer be able to perfectly clean the system especially if a wrong button or wrong option was executed by an inexperienced user when a warning prompt popped out during a scan. This happens most likely when a USB flash drive is inserted to a USB port. The antivirus could be configured to immediately scan any storage device attached to the system, but a wrong choice of commands or options on what to do with the antivirus warning could easilty upload the payloads of the the viruses residing in an infected flash drive.
The next time that the system is restarted, the virus could already become resident, waiting for its chances to spread like a ferocious wildfire.
To ensure protection, I highly recommend the use of third party software that locks a clean installation of the system. It is expected that before using the third party software, all application software had already been installed and configured. The job of the third party freezing software is to lock the system to its original, uninfected state.
I am fond of using WinRollBack that protects the system and maintains the original setup of the PC prior to its protection. I just have to protect the drive where the operating system is installed. Once WinRollBack is configured to protect the system drive, there would be no way that viruses can infect the system. Any infection is flushed out by the system once the PC is reboot.
Another is DeepFreeze. It also works like WinRollBack. Using any of the two could save the PC from harm caused by either viruses or test installations of software.
Get one now and try it.
