there is always a 'leftover'...

[circe801]

i am running v.5.19.5633 (64 bit) on win10.  under 'system', i have 'windows log files' checked, but after cleaning, i will reanalyze, and often, there is a small (under 10b) windows log file there.  if i clean again, the reported deleted files will be a larger one that originally reported, and sometimes there is also a 'windows search' file of 1024b removed that was not originally reported.  what is the reason for this??  thank you in advance for the assistance in helping me understand this.

[Nergal]

The file (and many of the files ccleaner removes) recreates itself when delete. The benefit of this is that the file (in your case your logs) is empty (no entries in the log). Thus ccleaner is doing its job, as is windows

[circe801]

new "leftover"--and i haven't changed anything--now, even after clearing cache in FF (shows 0 kb cache after) and again with CCleaner, there is a firefox cache file of a few hundred kb left.  i analyze and it shows, i clean and it doesn't show as having been deleted.  i analyze again, and there it is.  if CCleaner is set to delete all FF cache, cookies, etc., WHY is this all of a sudden (never happened before) there--and not being deleted during a clean?? why is it shown in analysis, and included in the 'files to be deleted' list, but is not in the 'files deleted' list.  and to me, this makes even less sense as it is FF and the program is closed, therefore, no files would be 'recreated' after cleaning. i hope  am being clear enough on this... thanks!!