Aloha Alan.
You have identified the root cause of my problem. The last accessed date for all the files that did not get deleted was within 24 hours of when I ran CCleaner. Thank you so much!
Now that I know this, I think the advanced option description "Only delete files in Windows Temp folders older than 24 hours" is incorrect. May I suggest that this be changed to "Only delete files in Windows Temp folders that have not been accessed in the last 24 hours". I realize that some folks may not understand the difference between created / updated / accessed time, but this wording is more accurate.
I now have the mystery of what program accessed these files in the 24 hours previous to running CCleaner. It does not appear to be my anti-virus, and I've disabled the Indexing Service. Maybe it was the Google Desktop. If anyone has any suggestions on what program(s) would be accessing some / all the files in the temp directories, I would appreciate it.
Mahalo nui loa (Thank you very much) for your assistance.
Harry Z
Perhaps YOU did it ! ! !
The DOS command DIR simply tells you information about the files.
BUT if you use Windows Explorer that will for some reason ACCESS the files.
I have just launched CMD.EXE and run DIR /T:A which by default shows my profile, i.e.
C:\Documents and Settings\Dad
Some files and folders were last accessed two days ago.
I launched Windows Explorer (which a long time ago I configured to display all 3 ages).
Windows explorer showed me the same access date as CMD.EXE.
I closed Windows Explorer and focus returned to CMD.EXE.
I repeated DIR /T:A and that now showed everything was accessed a few minutes ago.
W.E. was guilty of the access.
I opened W.E. and viewed another folder.
Some accessed dates were last year.
I hit the function key F5 and that immediately refreshed the display,
and everything had just been accessed.
W.E. is a control freak
If you select a 200 MB file and right click because you want to read its properties,
everything may freeze on you for many seconds whilst 200 MB of free space is wasted.
This is because the system decides to copy the 200 MB file into the current Restore Point.
This over-protective "nannying" may apply to executables,
especially if Windows File Protection gets involved (not that it should be involved with TEMP files.)
I agree that it would be better to use
"Only delete files in Windows Temp folders that have not been accessed in the last 24 hours"
but fear that "24 hours" is too precise so would actually prefer
"Only delete files in Windows Temp folders that have not been accessed in the last day"
I do not know whether CCleaner makes the effort to distinguish between files which were accessed 23 hours 59 minutes ago and 24 hours 1 minute ago, BUT the Accessed time stamp is always 00 hours 00 minutes for any FAT32 file, so if FAT32 is being cleaned then we can only tell the difference between today or previous days.
Regards
Alan