I Am Using HP Compaq System. How To Remove Virus?

First in order to make your system fast here are few tips

1. Clean your disk.
2. Remove all the cookies and temporary files.
3. Delete the history.
4. Clean the desktop (means very less files present on the desktop).

Now talking about the virus; well it depends what type of virus you have in your computer and in which sector. If the virus has corrupted your files and anti-virus can not repair it then you can attach the hard drive with another computer (which also have anti-virus) and then retrieve the data on that PC.

OR

Simply delete that file (without formatting the hard drive), and then use some recovery software like Recuva. This works well for recovering deleted files free of virus.

Reinstall windows afresh using xp bootable disk that is if you are using XP Windows.Press R to repair the windows . All your data will be safe.Then uninstall the previous version of anti virus you are using and reinstall the anti virus.The anti virus will be effective since all the previous system files have been replaced that were affected with the virus

You can use kaspersky antivirus to scan what virus in your system 1st,then do step by step, if still cannot settled then need reformat pc