

This is the path for Windows 7, other versions of Windows may use HKEY_CURRENT_USER\Software\Mozilla\Firefox\Extensions instead. Navigate to the key HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Mozilla\Firefox\Extensions using the folder structure on the left.Use Windows-R to bring up the run box, type regedit, and hit enter.The answer is by using the Windows Registry. So how did the avast! Online Security add-on get installed in first place if it is not located in one of Firefox's traditional add-on locations?

When you restart Firefox afterwards, the avast! Online Security entry is gone from the browser. When you have deleted the FF folder, or moved it to another location for safekeeping, you need to restart Firefox to complete the removal. The self-defense module is disabled then, and you can remove one or all of the extension folders under the WebRep structure afterwards. Avast displays an on-screen prompt afterwards where it wants you to verify that this is intended.You will receive a warning message, continue here.Remove the check mark from "Enable avast! self-defense module".Click on Troubleshooting after the avast! Settings open up.Click on the Settings link in the left sidebar.Open the Avast software interface on your system.To disable the self-defense mechanism, do the following: Note: before you go there, you need to disable the self-defense mechanism of the Avast application running on your system, or quit it, or remove the folders while booting into another operating system as they are protected otherwise and cannot be removed.
