Symptoms of a virus in a computer

Virus, Trojans, spams have brought down top IT companies to its knees. It's no doubt that these also degrade performance of one's computer. I have included herewith top symptoms of a computer being affected by a virus.

 

1. Your computer becomes slow. In Task Manager, unusual processes like svch0st.exe (instead of svchost.exe), lsasss.exe (instead of lsass.exe) would be running. Also, processes with absurd names are running.
2. Your computer behaves in unusual way. Suppose, if you click up button on tool bar, a warning message is displayed indicating that your computer is affected by virus. In fact, the virus or adware itself is displaying this message. The adware then directs you to its website suggesting buying their antivirus. You should be much careful of these advertisements.
3. Many often warning messages are displayed unusually. The warning message can be in different language like Arabic, Chinese, etc. This is also result of unwanted products installed in your computer.
4. Your computer takes a lot of time to start. A lot of programs are selected in startup. You can check this out by typing msconfig in run and clicking startup. Most probably, if your computer is affected by virus, msconfig is disabled. Either it closes suddenly after opening or message like "Msconfig has been disabled by Administrator".
5. Many often virus disables Task Manager. If you try to open task manager by pressing Ctrl + Alt + Del then a message like "Task Manager is disabled by Administrator" is displayed or Task Manager closes suddenly after opening. But also, it is likely that Task Manager be really disabled by someone by Group Policy (gpedit.msc).
6. Your registry is most like thing that is disabled by virus.
7. Critical error messages are displayed. Sometimes a blue screen is displayed showing memory dumping starting from 0 to 100%, after which computer restarts. It is also likely that your computer restarts automatically and many often.
8. The most likely symptom of affecting by adware is that, when you open Internet Explorer or other browsers, some messages are displayed like incorrect flash version is installed, compute is affected by virus, etc. It may be also likely that your page or home page is automatically redirected to some other page.
9. Unnecessary files are created in C: or system32 or windows folders.

Other normal symptoms are that hidden files and folders are not shown even if hidden files are selected to be shown in folder options, folder options is not displayed in control panel and tools menu of explorer, some folders are not allowed to open or while opening you are directed to somewhere else, sub-folders with same name same as folder and extension as .exe created.