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13 February 2007
Risk Impact:
Systems Affected:


Adware.MainSearch is an adware component that modifies the Web browser's default home page and search settings without the user's permission. It may delete other adware programs, and it may download an updated version of itself from a host site. The adware may also download back door programs.


The files on the system are detected as Adware.MainSearch.


This adware component must be manually installed or installed as a component of another program that you install

Antivirus Protection Dates

  • Initial Rapid Release version 02 October 2014 revision 022
  • Latest Rapid Release version 07 May 2019 revision 006
  • Initial Daily Certified version 23 September 2003
  • Latest Daily Certified version 07 May 2019 revision 008
  • Initial Weekly Certified release date 24 September 2003
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.

When Adware.MainSearch is executed, it performs the following actions:
  1. Modifies the Internet Explorer home page, so that when the browser is opened, it will, by default, load the advertising Web site.

  2. Modifies the Internet Explorer default search settings, so that any default search attempt would be directed to a particular controlling server, which is often affiliated with the advertiser.

  3. May delete other adware programs.

  4. May download an updated version of itself from a host site on the Internet.

  5. May download back door programs.

Note: Removing this adware component from the system will likely cause the program that installed it to not function as intended. The uninstaller generally identifies the programs that will not work after uninstallation.
  1. Update the definitions.
  2. Restart the computer in Safe mode.
  3. Run a full system scan and delete all the files detected as Adware.MainSearch.
  4. Restore the Internet Explorer settings.
For specific details on each of these steps, read the following instructions.
    1. To update the definitions
    To obtain the most recent definitions, start your Symantec program and run LiveUpdate.

    2. To restart the computer in Safe 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 instructions, read the document, "How to start the computer in Safe Mode ."

    3. To scan for and delete the files
    1. Start your Symantec antivirus program and run a full system scan.
    2. If any files are detected as Adware.MainSearch, click Delete.

      Note: If your Symantec antivirus product reports that it cannot delete a detected file, note the path and file name. Then use Windows Explorer to locate and delete the file.
    4. To restore the Internet Explorer settings
    1. Start Microsoft Internet Explorer.
    2. Connect to the Internet and go to the page that you want to set as your home page.
    3. Click Tools > Internet Options.
    4. In the Home page section of the General tab, click Use Current > OK.
    5. Click the Programs tab > Reset Web Settings.