The VRDB only protects certain files, .exe, dll and other system files, it doesn’t protect data files or all files, it is not a back-up program, so there are going to be many occasions where repair won’t be an option. See the avast help file, Healing, VRDB.
Only true virus infection can be repaired, e.g. when a virus infects a file it adds a small part to it, provided that file is one that avast’s VRDB would monitor and you have run the VRDB, then it may be possible to repair the file to its uninfected state.
However, for the most part so called viruses, trojans (adware/spyware/malware, etc.) can’t be repaired because the complete content of the file is malicious.
So without it if under normal circumstances a file might be protected by the VRDB if infected a repair might be possible, without that protection a repair is highly unlikely.
The default VRDB generation is 21 days. Personally I prefer to choose when to Generate VRDB at a time of my choosing. I do a weekly system maintenance and every other week I do a manual ‘Generate VRDB Now.’ I have the screen saver option checked and since I don’t use a screen saver it will never run automatically only when I use the Generate Now.
VRDB is a generic method, storing file parts that are often target of virus infections. So, it is capable of fixing even some brand new virus infections. However, it also means that it fails on some others (that use special infection methods, for example). So, it’s possible that VRDB doesn’t work for this particular virus… (and I’m afraid Cleaner won’t help either - it’s a handy tool, but with a very limited set of supported malware, and Luder is not one of them).
Actually, VRDB scans all the local hard disks for executable files and stores some info about them. So, it doesn’t care if the files belong to Win98, Win2000, or to a third-party application (as long as it is able to access the files - i.e. NTFS partitions certainly won’t be scanned from Win98 OS).
The rest, however, is true - VRDB is not a backup system, the stored information is very small (not the whole files). Besides, only Win32 executables are processed. The VRDB data are stored in \Data\Integ\avast.int
So it’s not a backup utility, but a restore feature of avast.
VRDB waits 8 seconds to consider the computer idle, meaning that VRDB will start generating when mouse is not moved (and keyboard not pressed) for 8 seconds. If you give any input to your PC within these 8 sec VRDB will NOT start generating.
I suggest you use the VRDB generation while the screen saver is running (if you use one).