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).
- Update the virus definitions.
- Run a full system scan and delete all the files detected as W32.Mytob.F@mm .
- Delete any values added to the registry.
For specific 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:
When you are completely finished with the removal procedure and are satisfied that the threat has been removed, reenable 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 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:
3. To scan for and delete the infected files
- 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 document: Virus Definitions (LiveUpdate).
- Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted daily. 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 document: Virus Definitions (Intelligent Updater).
The latest Intelligent Updater virus definitions can be obtained here: Intelligent Updater virus definitions. For detailed instructions read the document: How to update virus definition files using the Intelligent Updater.
Note: If you see an error, such as LU1418, when you try to run LiveUpdate and you cannot get the Web site hosting the Intelligent Updater, it is likely that the worm has modified the Hosts file. You can either download and install LiveUpdate 2.5, which can remove Symantec entries from that file, or you can edit it yourself. See the instructions for both in the "Additional Information" section below.
4. To delete the value from the registry
- 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.Mytob.F@mm, click Delete.
Note: If your Symantec antivirus product reports that it cannot delete an infected file, Windows may be using the file. To fix this, run the scan in Safe mode. For instructions, read the document: How to start the computer in Safe Mode. Once you have restarted in Safe mode, run the scan again.
After the files are deleted restart the computer in normal mode and proceed with section 4.
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 subkeys only. For instructions refer to the document: How to make a backup of the Windows registry.
- Click Start > Run.
- Type regedit
- Click OK.
- Navigate to the subkeys:
- In the right pane, delete the value:
"SVCHOST" = "taskgmr.exe"
- Exit the Registry Editor.