A common sign of a virus is, your computer is much slower than normal computer performance (Reasons why windows 7 performs slow). Some viruses can cause damage to Windows or some of your programs. Sometime it is occurring by the minimum requirement of computer resource like RAM size, processor version etc. But sometime there will a serious virus. The results of this, it damage your important disk & file data unexpectedly, programs starting or closing automatically, or Windows shutting down suddenly, then you would need to remove shutdown virus from your PC.
If your computer is infected with a virus, you'll want to remove it as quickly as possible. A fast way to check for viruses is to use an online scanner & virus removal. If your windows 7 computer is infected with a hard-hitting virus and you aren't able to access the Internet or run any programs, perhaps you should consider reformatting your computer's hard drive.
However, if you choose to reformat your computer's hard drive, you will lose all of your files and data, so I would suggest that you back up all of the files and data that you would like to keep before you reformat.
There are a system restore is a feature in Windows 7 roll back the system to a previous system state. Windows 7 include a startup repair that allows PC users to recover by starting up Windows. System Restore and Recovery Console options allow people to eliminate malware infections without the need of using antivirus or anti-malware programs.
Here some more things you should be try to remove a computer virus:
1. First you should turn off your windows 7 system restore feature before you try to clean the computer to avoid re-infecting it once you’ve removed a virus. Once you’ve removed all viruses from your windows 7 computer, you can turn System Restore back. (how to use backup and restore in windows 7)
2. If you don’t have antivirus software installed, use an online virus removal service.
3. You need aware with the manually virus removal process but it a technical process but you can do it if you have good experience with Windows registry and you know how to view and delete system and program files in Windows.
4. Always use a malicious software removal tool that scans your computer for most new viruses and malicious software.
See also: Fix Windows 7 hang up >>