How I remove virus from atapi.sys file?

Hi,
I use windows vista as operating system, but after the new installation of Vista my computer show me Windows security center give me error popup like file atapi.sys has been attacked by a Trojan. That time I installed windows 7. AVG. but windows keeps popping then I use McAfee antivirus but then also I get this virus, after the installation of McAfee antivirus I update also. But still it will give me error. so tell me what should I do? How I remove virus from atapi.sys file?

Solving this problem download combofix and run on your system and it will disinfect that file and remove all this type hidden virus problem which was you don’t know any where in your system. This file will automatically scan all this type of problem in your computer and using this you may clean your system, I think using this solution you solve your problem properly.

Use following steps for solving this problem

1. Go to Start > Run > type Notepad.exe and click OK to open Notepad.
2. Type or Copy following text in this notepad file

Code:
KillAll::
FCopy::
C:\Windows\ERDNT\cache\atapi.sys | C:\Windows\System32\drivers\atapi.sys

3. Then save this file with name of CFScript.txt , save this file on desktop.
4. Then drag the CFScript into ComboFix.exe that time ComboFix.exe will scan and remove all the problem and after that restart your computer and that time you not get any error message.

I also face this same problem for solving this problem I download the Filefind By Attribune file and run on my computer and use following steps
http://www.atribune.org/downloads/FileFind.zip
• open zip file and extract the setup then double click on FileFind.exe
• In search text box enter the infected file path eg. “type C:\”
• In the next search box enter the files to search “type atapi.sys”
• Then click on find button then it will automatically search this file
•if this files will able to find by this application then click on Export.
• This application will save this file in your “C” drive with the text files extension as Export.txt.
then open this file and delete all the code from this file and save it and save as this file atapi.sys and save in your system where your old file in currently
• When you copying this file that time system as you for replace this file or not then replace old file with this file then restart the computer and when you start your computer that time you not getting this error message.
I think this solution will help you to solve your problem.

Use following steps for downloading this problem
Download the F-Secure Blacklight (fsbl.exe) file
ftp://ftp.f-secure.com/anti-virus/tools/fsbl.exe
Then run on your computer and save to your C:\ drive.
• Open a command prompt for that type “cmd” for that use Start > Run and typing: cmd
• Then type C:\fsbl.exe /expert then press enter, it’s for starting this application.
• Accept the agreement then click "Next" and Click "Scan".
• After completing the scanning then click next and then click on Exit.
• This application create the log file in C:\ drive named "fsbl-dateandtime.log" name of this file is current date and time.
• In this log file you get some list of items.
• Here you see atapi.sys and then copy path of this files and then delete this file.
• And restart the computer I think this solution will help you to solve your problem.