W32.HLLW.Warpigs.B - Removal

The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.

1. Disable System Restore (Windows XP).
2. Update the virus definitions.
3. Restart the computer in Safe mode with command prompt.
4. Delete the values that were added to the registry. Restart the computer.
5. Run a full system scan and delete all the files detected as W32.HLLW.Warpigs.
6. Edit the modified System.ini file. (Windows 95/98/Me).
   

For specific details on each of these steps, read the following instructions.

1. Disabling System Restore (Windows Me/XP)
If you are running Windows Me or Windows XP, we recommend that you temporarily turn off System Restore. Windows Me/XP uses this feature, which is enabled by default, to restore the files on your computer in case they become damaged. If a virus, worm, or Trojan infects a computer, System Restore may back up the virus, worm, or Trojan on the computer.

Windows prevents outside programs, including antivirus programs, from modifying System Restore. Therefore, antivirus programs or tools cannot remove threats in the System Restore folder. As a result, System Restore has the potential of restoring an infected file on your computer, even after you have cleaned the infected files from all the other locations.

Also, a virus scan may detect a threat in the System Restore folder even though you have removed the threat.

For instructions on how to turn off System Restore, read your Windows documentation, or one of the following articles:

• "How to disable or enable Windows Me System Restore"
• "How to turn off or turn on Windows XP System Restore"

For additional information, and an alternative to disabling Windows Me System Restore, see the Microsoft Knowledge Base article, "Antivirus Tools Cannot Clean Infected Files in the _Restore Folder," Article ID: Q263455.

2. Updating the virus definitions
Symantec Security Response fully tests all the virus definitions for quality assurance before they are posted to our servers. There are two ways to obtain the most recent virus definitions:

• Running LiveUpdate, which is the easiest way to obtain virus definitions: These virus definitions are posted to the LiveUpdate servers once each week (usually on Wednesdays), unless there is a major virus outbreak. To determine whether definitions for this threat are available by LiveUpdate, refer to the Virus Definitions (LiveUpdate).
• Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted on U.S. business days (Monday through Friday). You should download the definitions from the Symantec Security Response Web site and manually install them. To determine whether definitions for this threat are available by the Intelligent Updater, refer to the Virus Definitions (Intelligent Updater).
  
  The Intelligent Updater virus definitions are available: Read "How to update virus definition files using the Intelligent Updater" for detailed instructions.

3. Restarting the computer in Safe mode with command prompt

1. Shut down the computer and turn off the power.
2. Wait at least 30 seconds.
3. Follow the instructions for your operating system:
   • Windows XP: Restart the computer. The computer begins processing a set of instructions known as the Basic Input/Output System (BIOS). The information displayed depends on the BIOS manufacturer. Some computers display a progress bar that refers to the word BIOS, while others may not display any indication that this process is occuring. As soon as the BIOS has finished loading, begin tapping the F8 key on your keyboard. Continue to do so until the Windows XP Advanced Options menu appears.
   • Windows 2000: Restart the computer. When you see the black-and-white Starting Windows bar at the bottom of the screen, start tapping the F8 key. The Windows 2000 Advanced Options Menu appears.
     
4. Using the up and down arrow keys, select Safe mode with command prompt, and then press Enter. After some time, the words Safe Mode will appear in all four corners of the screen. Continue to wait until a command prompt appears. When it does, proceed to the next section.

4. Deleting the value from the registry

CAUTION: Symantec strongly recommends that you back up the registry before making any changes to it. Incorrect changes to the registry can result in permanent data loss or corrupted files. Modify the specified keys only. Read the document, "How to make a backup of the Windows registry," for instructions.

1. At the command prompt, type the following and then press Enter:
   
   Regedit
   
   
2. Navigate to the key:
   
   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
   
   
3. In the right pane, delete the value:
   
   "windowsupdate"="winupdate.exe"
   
   
4. Navigate to the key:
   
   HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnce
   
   
5. In the right pane, delete the value:
   
   "windowsupdate"="winupdate.exe"
   
   
6. Navigate to the key:
   
   HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Winlogon
   
   
7. In the right pane, double-click: Shell
   
   
8. Change:
   
   "explorer.exe winupdate.exe"
   
   to:
   
   "explorer.exe"
   
   
9. Exit the Registry Editor.
10. Restart the computer and allow it to start normally.

5. Scanning for and deleting the infected files

1. Start your Symantec antivirus program and make sure that it is configured to scan all the files.
   • For Norton AntiVirus consumer products: Read the document, "How to configure Norton AntiVirus to scan all files."
   • For Symantec AntiVirus Enterprise products: Read the document, "How to verify that a Symantec Corporate antivirus product is set to scan all files."
2. Run a full system scan.
3. If any files are detected as infected with W32.HLLW.Warpigs.B, click Delete.

6. Editing the System.ini file
If you are running Windows 95/98/Me, follow these steps:

1. The function you perform depends on your operating system:
   • Windows 95/98: Go to step b.
   • Windows Me: If you are running Windows Me, the Windows Me file-protection process may have made a backup copy of the Win.ini file that you need to edit. If this backup copy exists, it will be in the C:\Windows\Recent folder. Symantec recommends that you delete this file before continuing with the steps in this section. To do this:
     1. Start Windows Explorer.
     2. Browse to and select the C:\Windows\Recent folder.
     3. In the right pane, select the System.ini file and delete it. The System.ini file will be regenerated when you save your changes to it in step f.
        
        
2. Click Start, and then click Run.
3. Type the following, and then click OK.
   
   edit c:\windows\system.ini
   
   (The MS-DOS Editor opens.)
   
   NOTE: If Windows is installed in a different location, make the appropriate path substitution.
   
   
4. In the [boot] section of the file, look for a line similar to:
   
   shell = Explorer.exe winupdate.exe
   
   
5. If this line exists, delete everything to the right of Explorer.exe.
   
   When you are done, it should look like:
   
   shell = Explorer.exe
   
   
6. Click File, and then click Save.
7. Click File, and then click Exit.

Technical Details