I do not know what a computer virus is and the sign to identify a computer infected with virus. I hope that Bkav can give me the answer.
Computer virus is a software program that can copy itself from one infected object to another object (the object can be program files, text files, etc.). After infecting successfully, virus can slow down the computer, damage infected files, lead to data loss, system errors and so on.
Virus can also utilize victims' computers to illegally advertise, send spam, cause discomfort to users, cause information insecurity, steal personal information, account information and credit numbers. Some viruses also take advantage of victims' computers to create botnets to attack servers and other websites.
Here are some signs to identify the infected computer:
+ The opening of files and applications is slow.
+ Strange websites automatically appear as browsing.
+ Web browsing is slow, the display of website’s content is slow too.
+ Advertising pages automatically pop up; Desktop screen is changed.
+ The right corner of the screen shows a yellow triangle warning: "Your computer is infected", or appears a "Virus Alert" window and so on.
+ Strange files are automatically generated when you open USB drives.
+ Files with .exe extension whose names match the names of directories appear.
In addition, there are many hidden viruses running with the system and there are no special or unusual signs, so it is difficult for users to identify the computer is infected.
Therefore, to ensure safety for your computer, you should choose a good antivirus software to install and use regularly and permanently for your computer. Good antivirus software must meet all criteria: being licensed, updating new versions regularly, providing direct technical support from the manufacturer in case of problem related to virus.