Background info courtesy of DonnaB Thank you
As for TFC, this is a tidbit of an article I found a while back by a MicroSoft MVP.
TFC (Temp File Cleaner) will clear out all temp folders for all user accounts (temp, IE temp, java, FF, Opera, Chrome, Safari), including Administrator, All Users, LocalService, NetworkService, and any other accounts in the user folder. It also cleans out the %systemroot%\temp folder and checks for .tmp files in the %systemdrive% root folder, %systemroot%, and the system32 folder (both 32bit and 64bit on 64bit OSs). It shows the amount removed for each location found (in bytes) and the total removed (in MB).
Before running, it will stop Explorer and all other running applications. When finished, if a reboot is required the user must reboot to finish clearing any in-use temp files.
-- TFC only cleans temp folders.
-- TFC will not clean URL history, prefetch, or cookies. Depending on how often someone cleans their temp folders, their system hardware, and how many accounts are present, it can take anywhere from a few seconds to a minute or more. TFC will completely clear all temp files where other temp file cleaners may fail.