Ronda
The Chest is located (on a Windows XP system) at C:\Documents and Settings\All Users\Application Data\Alwil Software\Avast5\chest. It's a special folder that avast! automatically set up when you installed it. The following is from the avast! help file:
The virus chest can be thought of as a folder on your hard disk with special properties, that make it a safe, isolated place for storing potentially harmful files. You can work with the files in the virus chest, with some security restrictions.
The main feature of the virus chest is complete isolation from the rest of the operating system. No outside process, such as a virus, can access the files inside the chest and as files inside the chest cannot be run, there is no danger in storing files there.
As a result of its unique properties, the virus chest is effectively a "quarantine" area which can therefore be used for various purposes:
Storing viruses - if avast! finds a virus and you decide not to delete it for some reason, you will be offered the option of moving it to the virus chest. With the virus in the chest, you can be sure that it will not be run, accidentally or otherwise.
Storing suspicious files - the chest is useful for storing suspicious files for later analysis.
Storing copies of other files which need to be kept separate from the rest of the system.
You can adjust some of the properties of the Chest by using the "Settings" options of avast. Other than those settings there is nothing else to be concerned with - avast! will manage the Chest automatically.