W32.Opaserv.AE.Worm - Removal

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

1. Update the virus definitions.
2. Disconnect from the network, if connected.
3. Disable System Restore (Windows Me/XP).
4. Restart the computer in Safe mode or VGA mode.
5. Run a full system scan and delete all the files detected as W32.Opaserv.AE.Worm.
6. Delete the value that was added to the registry.
7. Edit the Win.ini file.
   

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

1. 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.

2. Disconnecting from the network
If you are on a network, or have a full-time connection to the Internet, such as DSL or Cable modem, disconnect the computer from the network and the Internet. Disable sharing before reconnecting computers to the network or to the Internet. Because this worm spreads by using shared folders on networked computers, to ensure that the worm does not re-infect the computer after it has been removed, remove all the shares, clean all the computers on the network, patch all the systems, and update the definitions on all the computers before you reconnect to the network or re-enable shares.

For instructions, see your Windows documentation, or the document, "How to configure shared Windows folders for maximum network protection."

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IMPORTANT:

• Do not skip this step. You must disconnect from the network before attempting to remove this worm.
• For additional information on file sharing, read your Windows documentation or the document How to configure shared Windows folders for maximum network protection.
• When you have finished the removal procedure, if you decide to re-enable file sharing, Symantec suggests that you do not share the root of drive C. Share specific folders instead. These shares must be password-protected with a secure password. Do not use a blank password.
  
  Also, before doing so, if you are using Windows 95/98/Me, you must download and install the Microsoft patch from:
  
  http://www.microsoft.com/technet/security/bulletin/MS00-072.asp

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3. 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"

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Note: When you are completely finished with the removal procedure and are satisfied that the threat has been removed, re-enable System Restore by following the instructions in the aforementioned documents.

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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.

4. Restarting the computer in Safe mode or VGA mode
Shut down the computer and turn off the power. Wait for at least 30 seconds, and then restart the computer in Safe mode or VGA mode.

• For Windows 95, 98, Me, 2000, or XP users, restart the computer in Safe mode. For instructions, read the document, "How to start the computer in Safe Mode."
• For Windows NT 4 users, restart the computer in VGA mode.

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.Opaserv.AE.Worm, click Delete.

6. Deleting the value from the registry

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WARNING: 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.

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1. Click Start, and then click Run. (The Run dialog box appears.)
2. Type regedit
   
   Then click OK. (The Registry Editor opens.)
   
   
3. Navigate to the key:
   
   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run
   
   
4. In the right pane, delete the values:
   
   • Natal
   • Natal!Old
     
     
5. Exit the Registry Editor.
   

7. Editing the Win.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 Win.ini file and delete it. The Win.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\win.ini
   
   (The MS-DOS Editor opens.)
   
   

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   Note: If Windows is installed in a different location, make the appropriate path substitution.

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4. In the [windows] section of the file, look for a line similar to:
   
   run=c:\Windows\Natal.scr
   
   or:
   
   run=c:\lammer!
   
   
5. If this line exists, delete everything to the right of "run=".
   
   When you are done, it should look like:
   
   run=
   
   
6. Click File, and then click Save.
7. Click File, and then click Exit.

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Note: There have been several reports of infections by this worm in which the worm itself was infected with a virus, which then also spread to the infected computer. For this reason, we suggest that after you have finished removing W32.Opaserv.AE.Worm, that you run a full system scan. If any files are detected as infected with a different threat, go to http://securityresponse.symantec.com/avcenter/vinfodb.html, enter the name of the detection in the field, and then click search. Open the document, if one is found, and follow any removal instructions.

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Technical Details