Nikilet,
I have read through your previous post. In it you stated that you could not find ashchest.exe, only ashchest.dll.
I don't know what operating system you are using, but on XP ashchest.exe and ashchest.dll should both be found in C:\Program Fiules\Alwil Software]Avast4, so if you are using XP and the latest version of avast! 4.8.1201 and you can't find ashchest.exe, I would start looking at why this file is missing.
I can't remember whether you said you had carried out a repair of Avast. If you haven't then it would perhaps be worth a try. If you have tried a repair then perhaps you need to consider obtaining a fresh downloaded of the current version of avast, then completely uninstalling Avast, clearing out all traces of the old installation and then reinstalling the product.
I seem to remember something about "Generate VRDB only when screen saver is running" applying when it is an avast screen saver, not just any screen saver, but I may have this wrong. I have mine set to generate when the computer is idle. On a slow PC it will take some time to complete.