This has no doubt been asked and answered somewhere here a zillion times in the past (maybe I was even involved), but I’m too old and lazy to set up a proper search. :-[
On rare occasions, probably when there’s something major come through from MS Update, I’ll see additional copies of one or more of the system files (3 files, on my XP system) added to the chest.
Assuming I do regular scans and my system is very likely clean, is it safe to assume I can delete from the chest the older copy/copies of such system file duplicates?
Yes, you can delete them.
If Windows updates changes one of them, they would be added to Chest again (backup) as it is a new version of that target three System files.
Well personally I would just leave them there (hard disk space is hardly an issue), I have 3 copies of kernel32.dll, 1 winsock.dll and 1 wsock32.dll you can see the transfer dates they were added to the system files section of the chest.
If you ever rolled back a security update, if you deleted the previous copy in the chest might not be available if the original got infected.
OK, I have pretty much the same thing but what confuses me is the “last changed” date is the same as the changed dates in the actual windows\system32 folder. Are the files in the virus chest copies of those files or views of the same file? In other words deleting them won’t delete the files in the windows\system32 folder?
They should be copies of different versions of the same file in time, I mean, when updated the file could be added again into Chest.
For sure, deleting any file into Chest do not download the copy of the system file left behind. They’re backup of the original files. Anyway, it won’t harm if you let them there…
When you do a windows update it may change one or more of these originals and in that case avast takes another copy of the new file, this allows if for some reason you roll back/uninstall an update that updated one of the files, avast still has a back-up copy.
Personally I would leave them there as they don’t take up much disk space.