REMOVAL
Removal using the Removal Tool
Symantec Security Response has developed a
removal tool to clean the infections of W32.HLLW.Gaobot.AJD. This is the preferred method in most cases.
Manual Removal
The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.
- Disable System Restore (Windows Me/XP).
- Delete the lines that were added to the Windows Hosts file.
- Update the virus definitions.
- Restart the computer in Safe mode or VGA mode.
- Run a full system scan and delete all the files detected as W32.Gaobot.AJD.
- Reverse the changes made to the registry.
For details on each of these steps, read the following instructions.
1. To disable 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:
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.
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. To delete the added lines from the Windows Hosts file
Note: The location of the Hosts file may vary and some computers may not have this file. For example, if the file exists in Windows 98, it will usually be in C:\Windows; and it is located in the C:\WINNT\system32\drivers\etc folder in Windows 2000. There may also be multiple copies of this file in different locations.
Follow the instructions for your operating system:
- Windows 95/98/Me/NT/2000
- Click Start, point to Find or Search, and then click Files or Folders.
- Make sure that "Look in" is set to (C:) and that "Include subfolders" is checked.
- In the "Named" or "Search for..." box, type:
hosts
- Click Find Now or Search Now.
- For each Hosts file that you find, right-click the file, and then click "Open With."
- Deselect the "Always use this program to open this program" check box.
- Scroll through the list of programs and double-click Notepad.
- When the file opens, delete all the entries in the Hosts file, except for the following line:
127.0.0.1 localhost
- Close Notepad and save your changes when prompted.
- Windows XP
- Click Start, and then click Search.
- Click All files and folders.
- In the "All or part of the file name" box, type:
hosts
- Verify that "Look in" is set to "Local Hard Drives" or to (C:).
- Click "More advanced options."
- Check "Search system folders."
- Check "Search subfolders."
- Click Search.
- Click Find Now or Search Now.
- For each Hosts file that you find, right-click the file, and then click "Open With."
- Deselect the "Always use this program to open this program" check box.
- Scroll through the list of programs and double-click Notepad.
- When the file opens, delete all the entries in the Hosts file except for the following line:
127.0.0.1 localhost
- Close Notepad and save your changes when prompted.
3. To update 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.
4. To restart 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. To scan for and delete the infected files
- Start your Symantec antivirus program and make sure that it is configured to scan all the files.
- Run a full system scan.
- If any files are detected as infected with W32.Gaobot.AJD, click Delete.
6. To reverse the changes made to the registry
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.
- Click Start, and then click Run. (The Run dialog box appears.)
- Type regedit
Then click OK. (The Registry Editor opens.)
- Navigate to the keys:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\
RunServices
- In the right pane, delete the value:
"Automated Windows Updates"="wauclt.exe"
- Do one of the following:
- If you are running Windows NT/2000/XP, close the Registry Editor. Then restart the computer in Normal mode to complete the removal.
- If you are running Windows 95/98/Me, proceed with step f.
- Navigate to the key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\RunServices
- In the right pane, delete the value:
"windows"="hkey.exe"
- Close the Registry Editor. Then restart the computer in Normal mode to complete the removal.